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This is dash.info, produced by makeinfo version 6.5 from dash.texi.
This manual is for Dash version 2.18.0.
Copyright © 2012–2021 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with the Invariant Sections being “GNU General Public License,” and no Front-Cover Texts or Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”.INFO-DIR-SECTION EmacsSTART-INFO-DIR-ENTRY* Dash: (dash.info). A modern list library for GNU Emacs.END-INFO-DIR-ENTRY
File: dash.info, Node: Top, Next: Installation, Up: (dir)
Dash****
This manual is for Dash version 2.18.0.
Copyright © 2012–2021 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with the Invariant Sections being “GNU General Public License,” and no Front-Cover Texts or Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”.
* Menu:
* Installation:: Installing and configuring Dash.* Functions:: Dash API reference.* Development:: Contributing to Dash development.
Appendices
* FDL:: The license for this documentation.* GPL:: Conditions for copying and changing Dash.* Index:: Index including functions and macros.
— The Detailed Node Listing —
Installation
* Using in a package:: Listing Dash as a package dependency.* Fontification of special variables:: Font Lock of anaphoric macro variables.* Info symbol lookup:: Looking up Dash symbols in this manual.
Functions
* Maps::* Sublist selection::* List to list::* Reductions::* Unfolding::* Predicates::* Partitioning::* Indexing::* Set operations::* Other list operations::* Tree operations::* Threading macros::* Binding::* Side effects::* Destructive operations::* Function combinators::
Development
* Contribute:: How to contribute.* Contributors:: List of contributors.
File: dash.info, Node: Installation, Next: Functions, Prev: Top, Up: Top
1 Installation**************
Dash is available on GNU ELPA (https://elpa.gnu.org/) and MELPA(https://melpa.org/), and can be installed with the standard command‘package-install’ (*note (emacs)Package Installation::).
‘M-x package-install <RET> dash <RET>’ Install the Dash library.
Alternatively, you can just dump ‘dash.el’ in your ‘load-path’somewhere (*note (emacs)Lisp Libraries::).
* Menu:
* Using in a package:: Listing Dash as a package dependency.* Fontification of special variables:: Font Lock of anaphoric macro variables.* Info symbol lookup:: Looking up Dash symbols in this manual.
File: dash.info, Node: Using in a package, Next: Fontification of special variables, Up: Installation
1.1 Using in a package======================
If you use Dash in your own package, be sure to list it as a dependencyin the library’s headers as follows (*note (elisp)Library Headers::).
;; Package-Requires: ((dash "2.18.0"))
File: dash.info, Node: Fontification of special variables, Next: Info symbol lookup, Prev: Using in a package, Up: Installation
1.2 Fontification of special variables======================================
The autoloaded minor mode ‘dash-fontify-mode’ is provided for optionalfontification of anaphoric Dash variables (‘it’, ‘acc’, etc.) in EmacsLisp buffers using search-based Font Lock (*note (emacs)Font Lock::).In older Emacs versions which do not dynamically detect macros, theminor mode also fontifies calls to Dash macros.
To automatically enable the minor mode in all Emacs Lisp buffers,just call its autoloaded global counterpart ‘global-dash-fontify-mode’,either interactively or from your ‘user-init-file’:
(global-dash-fontify-mode)
File: dash.info, Node: Info symbol lookup, Prev: Fontification of special variables, Up: Installation
1.3 Info symbol lookup======================
While editing Elisp files, you can use ‘C-h S’ (‘info-lookup-symbol’) tolook up Elisp symbols in the relevant Info manuals (*note (emacs)InfoLookup::). To enable the same for Dash symbols, use the command‘dash-register-info-lookup’. It can be called directly when needed, orautomatically from your ‘user-init-file’. For example:
(with-eval-after-load 'info-look (dash-register-info-lookup))
File: dash.info, Node: Functions, Next: Development, Prev: Installation, Up: Top
2 Functions***********
This chapter contains reference documentation for the Dash API(Application Programming Interface). The names of all public functionsdefined in the library are prefixed with a dash character (‘-’).
The library also provides anaphoric macro versions of functions wherethat makes sense. The names of these macros are prefixed with twodashes (‘--’) instead of one.
For instance, while the function ‘-map’ applies a function to eachelement of a list, its anaphoric counterpart ‘--map’ evaluates a formwith the local variable ‘it’ temporarily bound to the current listelement instead.
;; Normal version. (-map (lambda (n) (* n n)) '(1 2 3 4)) ⇒ (1 4 9 16)
;; Anaphoric version. (--map (* it it) '(1 2 3 4)) ⇒ (1 4 9 16)
The normal version can, of course, also be written as in thefollowing example, which demonstrates the utility of both versions.
(defun my-square (n) "Return N multiplied by itself." (* n n))
(-map #'my-square '(1 2 3 4)) ⇒ (1 4 9 16)
* Menu:
* Maps::* Sublist selection::* List to list::* Reductions::* Unfolding::* Predicates::* Partitioning::* Indexing::* Set operations::* Other list operations::* Tree operations::* Threading macros::* Binding::* Side effects::* Destructive operations::* Function combinators::
File: dash.info, Node: Maps, Next: Sublist selection, Up: Functions
2.1 Maps========
Functions in this category take a transforming function, which is thenapplied sequentially to each or selected elements of the input list.The results are collected in order and returned as a new list.
-- Function: -map (fn list) Apply FN to each item in LIST and return the list of results.
This function’s anaphoric counterpart is ‘--map’.
(-map (lambda (num) (* num num)) '(1 2 3 4)) ⇒ (1 4 9 16) (-map #'1+ '(1 2 3 4)) ⇒ (2 3 4 5) (--map (* it it) '(1 2 3 4)) ⇒ (1 4 9 16)
-- Function: -map-when (pred rep list) Return a new list where the elements in LIST that do not match the PRED function are unchanged, and where the elements in LIST that do match the PRED function are mapped through the REP function.
Alias: ‘-replace-where’
See also: ‘-update-at’ (*note -update-at::)
(-map-when 'even? 'square '(1 2 3 4)) ⇒ (1 4 3 16) (--map-when (> it 2) (* it it) '(1 2 3 4)) ⇒ (1 2 9 16) (--map-when (= it 2) 17 '(1 2 3 4)) ⇒ (1 17 3 4)
-- Function: -map-first (pred rep list) Replace first item in LIST satisfying PRED with result of REP called on this item.
See also: ‘-map-when’ (*note -map-when::), ‘-replace-first’ (*note -replace-first::)
(-map-first 'even? 'square '(1 2 3 4)) ⇒ (1 4 3 4) (--map-first (> it 2) (* it it) '(1 2 3 4)) ⇒ (1 2 9 4) (--map-first (= it 2) 17 '(1 2 3 2)) ⇒ (1 17 3 2)
-- Function: -map-last (pred rep list) Replace last item in LIST satisfying PRED with result of REP called on this item.
See also: ‘-map-when’ (*note -map-when::), ‘-replace-last’ (*note -replace-last::)
(-map-last 'even? 'square '(1 2 3 4)) ⇒ (1 2 3 16) (--map-last (> it 2) (* it it) '(1 2 3 4)) ⇒ (1 2 3 16) (--map-last (= it 2) 17 '(1 2 3 2)) ⇒ (1 2 3 17)
-- Function: -map-indexed (fn list) Apply FN to each index and item in LIST and return the list of results. This is like ‘-map’ (*note -map::), but FN takes two arguments: the index of the current element within LIST, and the element itself.
This function’s anaphoric counterpart is ‘--map-indexed’.
For a side-effecting variant, see also ‘-each-indexed’ (*note -each-indexed::).
(-map-indexed (lambda (index item) (- item index)) '(1 2 3 4)) ⇒ (1 1 1 1) (--map-indexed (- it it-index) '(1 2 3 4)) ⇒ (1 1 1 1) (-map-indexed #'* '(1 2 3 4)) ⇒ (0 2 6 12)
-- Function: -annotate (fn list) Return a list of cons cells where each cell is FN applied to each element of LIST paired with the unmodified element of LIST.
(-annotate '1+ '(1 2 3)) ⇒ ((2 . 1) (3 . 2) (4 . 3)) (-annotate 'length '(("h" "e" "l" "l" "o") ("hello" "world"))) ⇒ ((5 "h" "e" "l" "l" "o") (2 "hello" "world")) (--annotate (< 1 it) '(0 1 2 3)) ⇒ ((nil . 0) (nil . 1) (t . 2) (t . 3))
-- Function: -splice (pred fun list) Splice lists generated by FUN in place of elements matching PRED in LIST.
FUN takes the element matching PRED as input.
This function can be used as replacement for ‘,@’ in case you need to splice several lists at marked positions (for example with keywords).
See also: ‘-splice-list’ (*note -splice-list::), ‘-insert-at’ (*note -insert-at::)
(-splice 'even? (lambda (x) (list x x)) '(1 2 3 4)) ⇒ (1 2 2 3 4 4) (--splice 't (list it it) '(1 2 3 4)) ⇒ (1 1 2 2 3 3 4 4) (--splice (equal it :magic) '((list of) (magical) (code)) '((foo) (bar) :magic (baz))) ⇒ ((foo) (bar) (list of) (magical) (code) (baz))
-- Function: -splice-list (pred new-list list) Splice NEW-LIST in place of elements matching PRED in LIST.
See also: ‘-splice’ (*note -splice::), ‘-insert-at’ (*note -insert-at::)
(-splice-list 'keywordp '(a b c) '(1 :foo 2)) ⇒ (1 a b c 2) (-splice-list 'keywordp nil '(1 :foo 2)) ⇒ (1 2) (--splice-list (keywordp it) '(a b c) '(1 :foo 2)) ⇒ (1 a b c 2)
-- Function: -mapcat (fn list) Return the concatenation of the result of mapping FN over LIST. Thus function FN should return a list.
(-mapcat 'list '(1 2 3)) ⇒ (1 2 3) (-mapcat (lambda (item) (list 0 item)) '(1 2 3)) ⇒ (0 1 0 2 0 3) (--mapcat (list 0 it) '(1 2 3)) ⇒ (0 1 0 2 0 3)
-- Function: -copy (list) Create a shallow copy of LIST.
(-copy '(1 2 3)) ⇒ (1 2 3) (let ((a '(1 2 3))) (eq a (-copy a))) ⇒ nil
File: dash.info, Node: Sublist selection, Next: List to list, Prev: Maps, Up: Functions
2.2 Sublist selection=====================
Functions returning a sublist of the original list.
-- Function: -filter (pred list) Return a new list of the items in LIST for which PRED returns non-nil.
Alias: ‘-select’.
This function’s anaphoric counterpart is ‘--filter’.
For similar operations, see also ‘-keep’ (*note -keep::) and ‘-remove’ (*note -remove::).
(-filter (lambda (num) (= 0 (% num 2))) '(1 2 3 4)) ⇒ (2 4) (-filter #'natnump '(-2 -1 0 1 2)) ⇒ (0 1 2) (--filter (= 0 (% it 2)) '(1 2 3 4)) ⇒ (2 4)
-- Function: -remove (pred list) Return a new list of the items in LIST for which PRED returns nil.
Alias: ‘-reject’.
This function’s anaphoric counterpart is ‘--remove’.
For similar operations, see also ‘-keep’ (*note -keep::) and ‘-filter’ (*note -filter::).
(-remove (lambda (num) (= 0 (% num 2))) '(1 2 3 4)) ⇒ (1 3) (-remove #'natnump '(-2 -1 0 1 2)) ⇒ (-2 -1) (--remove (= 0 (% it 2)) '(1 2 3 4)) ⇒ (1 3)
-- Function: -remove-first (pred list) Remove the first item from LIST for which PRED returns non-nil. This is a non-destructive operation, but only the front of LIST leading up to the removed item is a copy; the rest is LIST’s original tail. If no item is removed, then the result is a complete copy.
Alias: ‘-reject-first’.
This function’s anaphoric counterpart is ‘--remove-first’.
See also ‘-map-first’ (*note -map-first::), ‘-remove-item’ (*note -remove-item::), and ‘-remove-last’ (*note -remove-last::).
(-remove-first #'natnump '(-2 -1 0 1 2)) ⇒ (-2 -1 1 2) (-remove-first #'stringp '(1 2 "first" "second")) ⇒ (1 2 "second") (--remove-first (> it 3) '(1 2 3 4 5 6)) ⇒ (1 2 3 5 6)
-- Function: -remove-last (pred list) Remove the last item from LIST for which PRED returns non-nil. The result is a copy of LIST regardless of whether an element is removed.
Alias: ‘-reject-last’.
This function’s anaphoric counterpart is ‘--remove-last’.
See also ‘-map-last’ (*note -map-last::), ‘-remove-item’ (*note -remove-item::), and ‘-remove-first’ (*note -remove-first::).
(-remove-last #'natnump '(1 3 5 4 7 8 10 -11)) ⇒ (1 3 5 4 7 8 -11) (-remove-last #'stringp '(1 2 "last" "second")) ⇒ (1 2 "last") (--remove-last (> it 3) '(1 2 3 4 5 6 7 8 9 10)) ⇒ (1 2 3 4 5 6 7 8 9)
-- Function: -remove-item (item list) Return a copy of LIST with all occurrences of ITEM removed. The comparison is done with ‘equal’.
(-remove-item 3 '(1 2 3 2 3 4 5 3)) ⇒ (1 2 2 4 5) (-remove-item 'foo '(foo bar baz foo)) ⇒ (bar baz) (-remove-item "bob" '("alice" "bob" "eve" "bob")) ⇒ ("alice" "eve")
-- Function: -non-nil (list) Return a copy of LIST with all nil items removed.
(-non-nil '(nil 1 nil 2 nil nil 3 4 nil 5 nil)) ⇒ (1 2 3 4 5) (-non-nil '((nil))) ⇒ ((nil)) (-non-nil ()) ⇒ ()
-- Function: -slice (list from &optional to step) Return copy of LIST, starting from index FROM to index TO.
FROM or TO may be negative. These values are then interpreted modulo the length of the list.
If STEP is a number, only each STEPth item in the resulting section is returned. Defaults to 1.
(-slice '(1 2 3 4 5) 1) ⇒ (2 3 4 5) (-slice '(1 2 3 4 5) 0 3) ⇒ (1 2 3) (-slice '(1 2 3 4 5 6 7 8 9) 1 -1 2) ⇒ (2 4 6 8)
-- Function: -take (n list) Return a copy of the first N items in LIST. Return a copy of LIST if it contains N items or fewer. Return nil if N is zero or less.
See also: ‘-take-last’ (*note -take-last::).
(-take 3 '(1 2 3 4 5)) ⇒ (1 2 3) (-take 17 '(1 2 3 4 5)) ⇒ (1 2 3 4 5) (-take 0 '(1 2 3 4 5)) ⇒ ()
-- Function: -take-last (n list) Return a copy of the last N items of LIST in order. Return a copy of LIST if it contains N items or fewer. Return nil if N is zero or less.
See also: ‘-take’ (*note -take::).
(-take-last 3 '(1 2 3 4 5)) ⇒ (3 4 5) (-take-last 17 '(1 2 3 4 5)) ⇒ (1 2 3 4 5) (-take-last 1 '(1 2 3 4 5)) ⇒ (5)
-- Function: -drop (n list) Return the tail (not a copy) of LIST without the first N items. Return nil if LIST contains N items or fewer. Return LIST if N is zero or less.
For another variant, see also ‘-drop-last’ (*note -drop-last::).
(-drop 3 '(1 2 3 4 5)) ⇒ (4 5) (-drop 17 '(1 2 3 4 5)) ⇒ () (-drop 0 '(1 2 3 4 5)) ⇒ (1 2 3 4 5)
-- Function: -drop-last (n list) Return a copy of LIST without its last N items. Return a copy of LIST if N is zero or less. Return nil if LIST contains N items or fewer.
See also: ‘-drop’ (*note -drop::).
(-drop-last 3 '(1 2 3 4 5)) ⇒ (1 2) (-drop-last 17 '(1 2 3 4 5)) ⇒ () (-drop-last 0 '(1 2 3 4 5)) ⇒ (1 2 3 4 5)
-- Function: -take-while (pred list) Take successive items from LIST for which PRED returns non-nil. PRED is a function of one argument. Return a new list of the successive elements from the start of LIST for which PRED returns non-nil.
This function’s anaphoric counterpart is ‘--take-while’.
For another variant, see also ‘-drop-while’ (*note -drop-while::).
(-take-while #'even? '(1 2 3 4)) ⇒ () (-take-while #'even? '(2 4 5 6)) ⇒ (2 4) (--take-while (< it 4) '(1 2 3 4 3 2 1)) ⇒ (1 2 3)
-- Function: -drop-while (pred list) Drop successive items from LIST for which PRED returns non-nil. PRED is a function of one argument. Return the tail (not a copy) of LIST starting from its first element for which PRED returns nil.
This function’s anaphoric counterpart is ‘--drop-while’.
For another variant, see also ‘-take-while’ (*note -take-while::).
(-drop-while #'even? '(1 2 3 4)) ⇒ (1 2 3 4) (-drop-while #'even? '(2 4 5 6)) ⇒ (5 6) (--drop-while (< it 4) '(1 2 3 4 3 2 1)) ⇒ (4 3 2 1)
-- Function: -select-by-indices (indices list) Return a list whose elements are elements from LIST selected as ‘(nth i list)‘ for all i from INDICES.
(-select-by-indices '(4 10 2 3 6) '("v" "e" "l" "o" "c" "i" "r" "a" "p" "t" "o" "r")) ⇒ ("c" "o" "l" "o" "r") (-select-by-indices '(2 1 0) '("a" "b" "c")) ⇒ ("c" "b" "a") (-select-by-indices '(0 1 2 0 1 3 3 1) '("f" "a" "r" "l")) ⇒ ("f" "a" "r" "f" "a" "l" "l" "a")
-- Function: -select-columns (columns table) Select COLUMNS from TABLE.
TABLE is a list of lists where each element represents one row. It is assumed each row has the same length.
Each row is transformed such that only the specified COLUMNS are selected.
See also: ‘-select-column’ (*note -select-column::), ‘-select-by-indices’ (*note -select-by-indices::)
(-select-columns '(0 2) '((1 2 3) (a b c) (:a :b :c))) ⇒ ((1 3) (a c) (:a :c)) (-select-columns '(1) '((1 2 3) (a b c) (:a :b :c))) ⇒ ((2) (b) (:b)) (-select-columns nil '((1 2 3) (a b c) (:a :b :c))) ⇒ (nil nil nil)
-- Function: -select-column (column table) Select COLUMN from TABLE.
TABLE is a list of lists where each element represents one row. It is assumed each row has the same length.
The single selected column is returned as a list.
See also: ‘-select-columns’ (*note -select-columns::), ‘-select-by-indices’ (*note -select-by-indices::)
(-select-column 1 '((1 2 3) (a b c) (:a :b :c))) ⇒ (2 b :b)
File: dash.info, Node: List to list, Next: Reductions, Prev: Sublist selection, Up: Functions
2.3 List to list================
Functions returning a modified copy of the input list.
-- Function: -keep (fn list) Return a new list of the non-nil results of applying FN to each item in LIST. Like ‘-filter’ (*note -filter::), but returns the non-nil results of FN instead of the corresponding elements of LIST.
Its anaphoric counterpart is ‘--keep’.
(-keep #'cdr '((1 2 3) (4 5) (6))) ⇒ ((2 3) (5)) (-keep (lambda (n) (and (> n 3) (* 10 n))) '(1 2 3 4 5 6)) ⇒ (40 50 60) (--keep (and (> it 3) (* 10 it)) '(1 2 3 4 5 6)) ⇒ (40 50 60)
-- Function: -concat (&rest lists) Return a new list with the concatenation of the elements in the supplied LISTS.
(-concat '(1)) ⇒ (1) (-concat '(1) '(2)) ⇒ (1 2) (-concat '(1) '(2 3) '(4)) ⇒ (1 2 3 4)
-- Function: -flatten (l) Take a nested list L and return its contents as a single, flat list.
Note that because ‘nil’ represents a list of zero elements (an empty list), any mention of nil in L will disappear after flattening. If you need to preserve nils, consider ‘-flatten-n’ (*note -flatten-n::) or map them to some unique symbol and then map them back.
Conses of two atoms are considered "terminals", that is, they aren’t flattened further.
See also: ‘-flatten-n’ (*note -flatten-n::)
(-flatten '((1))) ⇒ (1) (-flatten '((1 (2 3) (((4 (5))))))) ⇒ (1 2 3 4 5) (-flatten '(1 2 (3 . 4))) ⇒ (1 2 (3 . 4))
-- Function: -flatten-n (num list) Flatten NUM levels of a nested LIST.
See also: ‘-flatten’ (*note -flatten::)
(-flatten-n 1 '((1 2) ((3 4) ((5 6))))) ⇒ (1 2 (3 4) ((5 6))) (-flatten-n 2 '((1 2) ((3 4) ((5 6))))) ⇒ (1 2 3 4 (5 6)) (-flatten-n 3 '((1 2) ((3 4) ((5 6))))) ⇒ (1 2 3 4 5 6)
-- Function: -replace (old new list) Replace all OLD items in LIST with NEW.
Elements are compared using ‘equal’.
See also: ‘-replace-at’ (*note -replace-at::)
(-replace 1 "1" '(1 2 3 4 3 2 1)) ⇒ ("1" 2 3 4 3 2 "1") (-replace "foo" "bar" '("a" "nice" "foo" "sentence" "about" "foo")) ⇒ ("a" "nice" "bar" "sentence" "about" "bar") (-replace 1 2 nil) ⇒ nil
-- Function: -replace-first (old new list) Replace the first occurrence of OLD with NEW in LIST.
Elements are compared using ‘equal’.
See also: ‘-map-first’ (*note -map-first::)
(-replace-first 1 "1" '(1 2 3 4 3 2 1)) ⇒ ("1" 2 3 4 3 2 1) (-replace-first "foo" "bar" '("a" "nice" "foo" "sentence" "about" "foo")) ⇒ ("a" "nice" "bar" "sentence" "about" "foo") (-replace-first 1 2 nil) ⇒ nil
-- Function: -replace-last (old new list) Replace the last occurrence of OLD with NEW in LIST.
Elements are compared using ‘equal’.
See also: ‘-map-last’ (*note -map-last::)
(-replace-last 1 "1" '(1 2 3 4 3 2 1)) ⇒ (1 2 3 4 3 2 "1") (-replace-last "foo" "bar" '("a" "nice" "foo" "sentence" "about" "foo")) ⇒ ("a" "nice" "foo" "sentence" "about" "bar") (-replace-last 1 2 nil) ⇒ nil
-- Function: -insert-at (n x list) Return a list with X inserted into LIST at position N.
See also: ‘-splice’ (*note -splice::), ‘-splice-list’ (*note -splice-list::)
(-insert-at 1 'x '(a b c)) ⇒ (a x b c) (-insert-at 12 'x '(a b c)) ⇒ (a b c x)
-- Function: -replace-at (n x list) Return a list with element at Nth position in LIST replaced with X.
See also: ‘-replace’ (*note -replace::)
(-replace-at 0 9 '(0 1 2 3 4 5)) ⇒ (9 1 2 3 4 5) (-replace-at 1 9 '(0 1 2 3 4 5)) ⇒ (0 9 2 3 4 5) (-replace-at 4 9 '(0 1 2 3 4 5)) ⇒ (0 1 2 3 9 5)
-- Function: -update-at (n func list) Return a list with element at Nth position in LIST replaced with ‘(func (nth n list))‘.
See also: ‘-map-when’ (*note -map-when::)
(-update-at 0 (lambda (x) (+ x 9)) '(0 1 2 3 4 5)) ⇒ (9 1 2 3 4 5) (-update-at 1 (lambda (x) (+ x 8)) '(0 1 2 3 4 5)) ⇒ (0 9 2 3 4 5) (--update-at 2 (length it) '("foo" "bar" "baz" "quux")) ⇒ ("foo" "bar" 3 "quux")
-- Function: -remove-at (n list) Return a list with element at Nth position in LIST removed.
See also: ‘-remove-at-indices’ (*note -remove-at-indices::), ‘-remove’ (*note -remove::)
(-remove-at 0 '("0" "1" "2" "3" "4" "5")) ⇒ ("1" "2" "3" "4" "5") (-remove-at 1 '("0" "1" "2" "3" "4" "5")) ⇒ ("0" "2" "3" "4" "5") (-remove-at 2 '("0" "1" "2" "3" "4" "5")) ⇒ ("0" "1" "3" "4" "5")
-- Function: -remove-at-indices (indices list) Return a list whose elements are elements from LIST without elements selected as ‘(nth i list)‘ for all i from INDICES.
See also: ‘-remove-at’ (*note -remove-at::), ‘-remove’ (*note -remove::)
(-remove-at-indices '(0) '("0" "1" "2" "3" "4" "5")) ⇒ ("1" "2" "3" "4" "5") (-remove-at-indices '(0 2 4) '("0" "1" "2" "3" "4" "5")) ⇒ ("1" "3" "5") (-remove-at-indices '(0 5) '("0" "1" "2" "3" "4" "5")) ⇒ ("1" "2" "3" "4")
File: dash.info, Node: Reductions, Next: Unfolding, Prev: List to list, Up: Functions
2.4 Reductions==============
Functions reducing lists to a single value (which may also be a list).
-- Function: -reduce-from (fn init list) Reduce the function FN across LIST, starting with INIT. Return the result of applying FN to INIT and the first element of LIST, then applying FN to that result and the second element, etc. If LIST is empty, return INIT without calling FN.
This function’s anaphoric counterpart is ‘--reduce-from’.
For other folds, see also ‘-reduce’ (*note -reduce::) and ‘-reduce-r’ (*note -reduce-r::).
(-reduce-from #'- 10 '(1 2 3)) ⇒ 4 (-reduce-from #'list 10 '(1 2 3)) ⇒ (((10 1) 2) 3) (--reduce-from (concat acc " " it) "START" '("a" "b" "c")) ⇒ "START a b c"
-- Function: -reduce-r-from (fn init list) Reduce the function FN across LIST in reverse, starting with INIT. Return the result of applying FN to the last element of LIST and INIT, then applying FN to the second-to-last element and the previous result of FN, etc. That is, the first argument of FN is the current element, and its second argument the accumulated value. If LIST is empty, return INIT without calling FN.
This function is like ‘-reduce-from’ (*note -reduce-from::) but the operation associates from the right rather than left. In other words, it starts from the end of LIST and flips the arguments to FN. Conceptually, it is like replacing the conses in LIST with applications of FN, and its last link with INIT, and evaluating the resulting expression.
This function’s anaphoric counterpart is ‘--reduce-r-from’.
For other folds, see also ‘-reduce-r’ (*note -reduce-r::) and ‘-reduce’ (*note -reduce::).
(-reduce-r-from #'- 10 '(1 2 3)) ⇒ -8 (-reduce-r-from #'list 10 '(1 2 3)) ⇒ (1 (2 (3 10))) (--reduce-r-from (concat it " " acc) "END" '("a" "b" "c")) ⇒ "a b c END"
-- Function: -reduce (fn list) Reduce the function FN across LIST. Return the result of applying FN to the first two elements of LIST, then applying FN to that result and the third element, etc. If LIST contains a single element, return it without calling FN. If LIST is empty, return the result of calling FN with no arguments.
This function’s anaphoric counterpart is ‘--reduce’.
For other folds, see also ‘-reduce-from’ (*note -reduce-from::) and ‘-reduce-r’ (*note -reduce-r::).
(-reduce #'- '(1 2 3 4)) ⇒ -8 (-reduce #'list '(1 2 3 4)) ⇒ (((1 2) 3) 4) (--reduce (format "%s-%d" acc it) '(1 2 3)) ⇒ "1-2-3"
-- Function: -reduce-r (fn list) Reduce the function FN across LIST in reverse. Return the result of applying FN to the last two elements of LIST, then applying FN to the third-to-last element and the previous result of FN, etc. That is, the first argument of FN is the current element, and its second argument the accumulated value. If LIST contains a single element, return it without calling FN. If LIST is empty, return the result of calling FN with no arguments.
This function is like ‘-reduce’ (*note -reduce::) but the operation associates from the right rather than left. In other words, it starts from the end of LIST and flips the arguments to FN. Conceptually, it is like replacing the conses in LIST with applications of FN, ignoring its last link, and evaluating the resulting expression.
This function’s anaphoric counterpart is ‘--reduce-r’.
For other folds, see also ‘-reduce-r-from’ (*note -reduce-r-from::) and ‘-reduce’ (*note -reduce::).
(-reduce-r #'- '(1 2 3 4)) ⇒ -2 (-reduce-r #'list '(1 2 3 4)) ⇒ (1 (2 (3 4))) (--reduce-r (format "%s-%d" acc it) '(1 2 3)) ⇒ "3-2-1"
-- Function: -reductions-from (fn init list) Return a list of FN’s intermediate reductions across LIST. That is, a list of the intermediate values of the accumulator when ‘-reduce-from’ (*note -reduce-from::) (which see) is called with the same arguments.
This function’s anaphoric counterpart is ‘--reductions-from’.
For other folds, see also ‘-reductions’ (*note -reductions::) and ‘-reductions-r’ (*note -reductions-r::).
(-reductions-from #'max 0 '(2 1 4 3)) ⇒ (0 2 2 4 4) (-reductions-from #'* 1 '(1 2 3 4)) ⇒ (1 1 2 6 24) (--reductions-from (format "(FN %s %d)" acc it) "INIT" '(1 2 3)) ⇒ ("INIT" "(FN INIT 1)" "(FN (FN INIT 1) 2)" "(FN (FN (FN INIT 1) 2) 3)")
-- Function: -reductions-r-from (fn init list) Return a list of FN’s intermediate reductions across reversed LIST. That is, a list of the intermediate values of the accumulator when ‘-reduce-r-from’ (*note -reduce-r-from::) (which see) is called with the same arguments.
This function’s anaphoric counterpart is ‘--reductions-r-from’.
For other folds, see also ‘-reductions’ (*note -reductions::) and ‘-reductions-r’ (*note -reductions-r::).
(-reductions-r-from #'max 0 '(2 1 4 3)) ⇒ (4 4 4 3 0) (-reductions-r-from #'* 1 '(1 2 3 4)) ⇒ (24 24 12 4 1) (--reductions-r-from (format "(FN %d %s)" it acc) "INIT" '(1 2 3)) ⇒ ("(FN 1 (FN 2 (FN 3 INIT)))" "(FN 2 (FN 3 INIT))" "(FN 3 INIT)" "INIT")
-- Function: -reductions (fn list) Return a list of FN’s intermediate reductions across LIST. That is, a list of the intermediate values of the accumulator when ‘-reduce’ (*note -reduce::) (which see) is called with the same arguments.
This function’s anaphoric counterpart is ‘--reductions’.
For other folds, see also ‘-reductions’ (*note -reductions::) and ‘-reductions-r’ (*note -reductions-r::).
(-reductions #'+ '(1 2 3 4)) ⇒ (1 3 6 10) (-reductions #'* '(1 2 3 4)) ⇒ (1 2 6 24) (--reductions (format "(FN %s %d)" acc it) '(1 2 3)) ⇒ (1 "(FN 1 2)" "(FN (FN 1 2) 3)")
-- Function: -reductions-r (fn list) Return a list of FN’s intermediate reductions across reversed LIST. That is, a list of the intermediate values of the accumulator when ‘-reduce-r’ (*note -reduce-r::) (which see) is called with the same arguments.
This function’s anaphoric counterpart is ‘--reductions-r’.
For other folds, see also ‘-reductions-r-from’ (*note -reductions-r-from::) and ‘-reductions’ (*note -reductions::).
(-reductions-r #'+ '(1 2 3 4)) ⇒ (10 9 7 4) (-reductions-r #'* '(1 2 3 4)) ⇒ (24 24 12 4) (--reductions-r (format "(FN %d %s)" it acc) '(1 2 3)) ⇒ ("(FN 1 (FN 2 3))" "(FN 2 3)" 3)
-- Function: -count (pred list) Counts the number of items in LIST where (PRED item) is non-nil.
(-count 'even? '(1 2 3 4 5)) ⇒ 2 (--count (< it 4) '(1 2 3 4)) ⇒ 3
-- Function: -sum (list) Return the sum of LIST.
(-sum ()) ⇒ 0 (-sum '(1)) ⇒ 1 (-sum '(1 2 3 4)) ⇒ 10
-- Function: -running-sum (list) Return a list with running sums of items in LIST. LIST must be non-empty.
(-running-sum '(1 2 3 4)) ⇒ (1 3 6 10) (-running-sum '(1)) ⇒ (1) (-running-sum ()) error→ Wrong type argument: consp, nil
-- Function: -product (list) Return the product of LIST.
(-product ()) ⇒ 1 (-product '(1)) ⇒ 1 (-product '(1 2 3 4)) ⇒ 24
-- Function: -running-product (list) Return a list with running products of items in LIST. LIST must be non-empty.
(-running-product '(1 2 3 4)) ⇒ (1 2 6 24) (-running-product '(1)) ⇒ (1) (-running-product ()) error→ Wrong type argument: consp, nil
-- Function: -inits (list) Return all prefixes of LIST.
(-inits '(1 2 3 4)) ⇒ (nil (1) (1 2) (1 2 3) (1 2 3 4)) (-inits nil) ⇒ (nil) (-inits '(1)) ⇒ (nil (1))
-- Function: -tails (list) Return all suffixes of LIST
(-tails '(1 2 3 4)) ⇒ ((1 2 3 4) (2 3 4) (3 4) (4) nil) (-tails nil) ⇒ (nil) (-tails '(1)) ⇒ ((1) nil)
-- Function: -common-prefix (&rest lists) Return the longest common prefix of LISTS.
(-common-prefix '(1)) ⇒ (1) (-common-prefix '(1 2) '(3 4) '(1 2)) ⇒ () (-common-prefix '(1 2) '(1 2 3) '(1 2 3 4)) ⇒ (1 2)
-- Function: -common-suffix (&rest lists) Return the longest common suffix of LISTS.
(-common-suffix '(1)) ⇒ (1) (-common-suffix '(1 2) '(3 4) '(1 2)) ⇒ () (-common-suffix '(1 2 3 4) '(2 3 4) '(3 4)) ⇒ (3 4)
-- Function: -min (list) Return the smallest value from LIST of numbers or markers.
(-min '(0)) ⇒ 0 (-min '(3 2 1)) ⇒ 1 (-min '(1 2 3)) ⇒ 1
-- Function: -min-by (comparator list) Take a comparison function COMPARATOR and a LIST and return the least element of the list by the comparison function.
See also combinator ‘-on’ (*note -on::) which can transform the values before comparing them.
(-min-by '> '(4 3 6 1)) ⇒ 1 (--min-by (> (car it) (car other)) '((1 2 3) (2) (3 2))) ⇒ (1 2 3) (--min-by (> (length it) (length other)) '((1 2 3) (2) (3 2))) ⇒ (2)
-- Function: -max (list) Return the largest value from LIST of numbers or markers.
(-max '(0)) ⇒ 0 (-max '(3 2 1)) ⇒ 3 (-max '(1 2 3)) ⇒ 3
-- Function: -max-by (comparator list) Take a comparison function COMPARATOR and a LIST and return the greatest element of the list by the comparison function.
See also combinator ‘-on’ (*note -on::) which can transform the values before comparing them.
(-max-by '> '(4 3 6 1)) ⇒ 6 (--max-by (> (car it) (car other)) '((1 2 3) (2) (3 2))) ⇒ (3 2) (--max-by (> (length it) (length other)) '((1 2 3) (2) (3 2))) ⇒ (1 2 3)
File: dash.info, Node: Unfolding, Next: Predicates, Prev: Reductions, Up: Functions
2.5 Unfolding=============
Operations dual to reductions, building lists from a seed value ratherthan consuming a list to produce a single value.
-- Function: -iterate (fun init n) Return a list of iterated applications of FUN to INIT.
This means a list of the form:
(INIT (FUN INIT) (FUN (FUN INIT)) ...)
N is the length of the returned list.
(-iterate #'1+ 1 10) ⇒ (1 2 3 4 5 6 7 8 9 10) (-iterate (lambda (x) (+ x x)) 2 5) ⇒ (2 4 8 16 32) (--iterate (* it it) 2 5) ⇒ (2 4 16 256 65536)
-- Function: -unfold (fun seed) Build a list from SEED using FUN.
This is "dual" operation to ‘-reduce-r’ (*note -reduce-r::): while -reduce-r consumes a list to produce a single value, ‘-unfold’ (*note -unfold::) takes a seed value and builds a (potentially infinite!) list.
FUN should return ‘nil’ to stop the generating process, or a cons (A . B), where A will be prepended to the result and B is the new seed.
(-unfold (lambda (x) (unless (= x 0) (cons x (1- x)))) 10) ⇒ (10 9 8 7 6 5 4 3 2 1) (--unfold (when it (cons it (cdr it))) '(1 2 3 4)) ⇒ ((1 2 3 4) (2 3 4) (3 4) (4)) (--unfold (when it (cons it (butlast it))) '(1 2 3 4)) ⇒ ((1 2 3 4) (1 2 3) (1 2) (1))
File: dash.info, Node: Predicates, Next: Partitioning, Prev: Unfolding, Up: Functions
2.6 Predicates==============
Reductions of one or more lists to a boolean value.
-- Function: -any? (pred list) Return t if (PRED x) is non-nil for any x in LIST, else nil.
Alias: ‘-any-p’, ‘-some?’, ‘-some-p’
(-any? 'even? '(1 2 3)) ⇒ t (-any? 'even? '(1 3 5)) ⇒ nil (-any? 'null '(1 3 5)) ⇒ nil
-- Function: -all? (pred list) Return t if (PRED x) is non-nil for all x in LIST, else nil.
Alias: ‘-all-p’, ‘-every?’, ‘-every-p’
(-all? 'even? '(1 2 3)) ⇒ nil (-all? 'even? '(2 4 6)) ⇒ t (--all? (= 0 (% it 2)) '(2 4 6)) ⇒ t
-- Function: -none? (pred list) Return t if (PRED x) is nil for all x in LIST, else nil.
Alias: ‘-none-p’
(-none? 'even? '(1 2 3)) ⇒ nil (-none? 'even? '(1 3 5)) ⇒ t (--none? (= 0 (% it 2)) '(1 2 3)) ⇒ nil
-- Function: -only-some? (pred list) Return ‘t‘ if at least one item of LIST matches PRED and at least one item of LIST does not match PRED. Return ‘nil‘ both if all items match the predicate or if none of the items match the predicate.
Alias: ‘-only-some-p’
(-only-some? 'even? '(1 2 3)) ⇒ t (-only-some? 'even? '(1 3 5)) ⇒ nil (-only-some? 'even? '(2 4 6)) ⇒ nil
-- Function: -contains? (list element) Return non-nil if LIST contains ELEMENT.
The test for equality is done with ‘equal’, or with ‘-compare-fn’ if that’s non-nil.
Alias: ‘-contains-p’
(-contains? '(1 2 3) 1) ⇒ t (-contains? '(1 2 3) 2) ⇒ t (-contains? '(1 2 3) 4) ⇒ nil
-- Function: -same-items? (list list2) Return true if LIST and LIST2 has the same items.
The order of the elements in the lists does not matter.
Alias: ‘-same-items-p’
(-same-items? '(1 2 3) '(1 2 3)) ⇒ t (-same-items? '(1 2 3) '(3 2 1)) ⇒ t (-same-items? '(1 2 3) '(1 2 3 4)) ⇒ nil
-- Function: -is-prefix? (prefix list) Return non-nil if PREFIX is a prefix of LIST.
Alias: ‘-is-prefix-p’.
(-is-prefix? '(1 2 3) '(1 2 3 4 5)) ⇒ t (-is-prefix? '(1 2 3 4 5) '(1 2 3)) ⇒ nil (-is-prefix? '(1 3) '(1 2 3 4 5)) ⇒ nil
-- Function: -is-suffix? (suffix list) Return non-nil if SUFFIX is a suffix of LIST.
Alias: ‘-is-suffix-p’.
(-is-suffix? '(3 4 5) '(1 2 3 4 5)) ⇒ t (-is-suffix? '(1 2 3 4 5) '(3 4 5)) ⇒ nil (-is-suffix? '(3 5) '(1 2 3 4 5)) ⇒ nil
-- Function: -is-infix? (infix list) Return non-nil if INFIX is infix of LIST.
This operation runs in O(n^2) time
Alias: ‘-is-infix-p’
(-is-infix? '(1 2 3) '(1 2 3 4 5)) ⇒ t (-is-infix? '(2 3 4) '(1 2 3 4 5)) ⇒ t (-is-infix? '(3 4 5) '(1 2 3 4 5)) ⇒ t
-- Function: -cons-pair? (obj) Return non-nil if OBJ is a true cons pair. That is, a cons (A . B) where B is not a list.
Alias: ‘-cons-pair-p’.
(-cons-pair? '(1 . 2)) ⇒ t (-cons-pair? '(1 2)) ⇒ nil (-cons-pair? '(1)) ⇒ nil
File: dash.info, Node: Partitioning, Next: Indexing, Prev: Predicates, Up: Functions
2.7 Partitioning================
Functions partitioning the input list into a list of lists.
-- Function: -split-at (n list) Split LIST into two sublists after the Nth element. The result is a list of two elements (TAKE DROP) where TAKE is a new list of the first N elements of LIST, and DROP is the remaining elements of LIST (not a copy). TAKE and DROP are like the results of ‘-take’ (*note -take::) and ‘-drop’ (*note -drop::), respectively, but the split is done in a single list traversal.
(-split-at 3 '(1 2 3 4 5)) ⇒ ((1 2 3) (4 5)) (-split-at 17 '(1 2 3 4 5)) ⇒ ((1 2 3 4 5) nil) (-split-at 0 '(1 2 3 4 5)) ⇒ (nil (1 2 3 4 5))
-- Function: -split-with (pred list) Return a list of ((-take-while PRED LIST) (-drop-while PRED LIST)), in no more than one pass through the list.
(-split-with 'even? '(1 2 3 4)) ⇒ (nil (1 2 3 4)) (-split-with 'even? '(2 4 5 6)) ⇒ ((2 4) (5 6)) (--split-with (< it 4) '(1 2 3 4 3 2 1)) ⇒ ((1 2 3) (4 3 2 1))
-- Macro: -split-on (item list) Split the LIST each time ITEM is found.
Unlike ‘-partition-by’ (*note -partition-by::), the ITEM is discarded from the results. Empty lists are also removed from the result.
Comparison is done by ‘equal’.
See also ‘-split-when’ (*note -split-when::)
(-split-on '| '(Nil | Leaf a | Node [Tree a])) ⇒ ((Nil) (Leaf a) (Node [Tree a])) (-split-on ':endgroup '("a" "b" :endgroup "c" :endgroup "d" "e")) ⇒ (("a" "b") ("c") ("d" "e")) (-split-on ':endgroup '("a" "b" :endgroup :endgroup "d" "e")) ⇒ (("a" "b") ("d" "e"))
-- Function: -split-when (fn list) Split the LIST on each element where FN returns non-nil.
Unlike ‘-partition-by’ (*note -partition-by::), the "matched" element is discarded from the results. Empty lists are also removed from the result.
This function can be thought of as a generalization of ‘split-string’.
(-split-when 'even? '(1 2 3 4 5 6)) ⇒ ((1) (3) (5)) (-split-when 'even? '(1 2 3 4 6 8 9)) ⇒ ((1) (3) (9)) (--split-when (memq it '(&optional &rest)) '(a b &optional c d &rest args)) ⇒ ((a b) (c d) (args))
-- Function: -separate (pred list) Return a list of ((-filter PRED LIST) (-remove PRED LIST)), in one pass through the list.
(-separate (lambda (num) (= 0 (% num 2))) '(1 2 3 4 5 6 7)) ⇒ ((2 4 6) (1 3 5 7)) (--separate (< it 5) '(3 7 5 9 3 2 1 4 6)) ⇒ ((3 3 2 1 4) (7 5 9 6)) (-separate 'cdr '((1 2) (1) (1 2 3) (4))) ⇒ (((1 2) (1 2 3)) ((1) (4)))
-- Function: -partition (n list) Return a new list with the items in LIST grouped into N-sized sublists. If there are not enough items to make the last group N-sized, those items are discarded.
(-partition 2 '(1 2 3 4 5 6)) ⇒ ((1 2) (3 4) (5 6)) (-partition 2 '(1 2 3 4 5 6 7)) ⇒ ((1 2) (3 4) (5 6)) (-partition 3 '(1 2 3 4 5 6 7)) ⇒ ((1 2 3) (4 5 6))
-- Function: -partition-all (n list) Return a new list with the items in LIST grouped into N-sized sublists. The last group may contain less than N items.
(-partition-all 2 '(1 2 3 4 5 6)) ⇒ ((1 2) (3 4) (5 6)) (-partition-all 2 '(1 2 3 4 5 6 7)) ⇒ ((1 2) (3 4) (5 6) (7)) (-partition-all 3 '(1 2 3 4 5 6 7)) ⇒ ((1 2 3) (4 5 6) (7))
-- Function: -partition-in-steps (n step list) Return a new list with the items in LIST grouped into N-sized sublists at offsets STEP apart. If there are not enough items to make the last group N-sized, those items are discarded.
(-partition-in-steps 2 1 '(1 2 3 4)) ⇒ ((1 2) (2 3) (3 4)) (-partition-in-steps 3 2 '(1 2 3 4)) ⇒ ((1 2 3)) (-partition-in-steps 3 2 '(1 2 3 4 5)) ⇒ ((1 2 3) (3 4 5))
-- Function: -partition-all-in-steps (n step list) Return a new list with the items in LIST grouped into N-sized sublists at offsets STEP apart. The last groups may contain less than N items.
(-partition-all-in-steps 2 1 '(1 2 3 4)) ⇒ ((1 2) (2 3) (3 4) (4)) (-partition-all-in-steps 3 2 '(1 2 3 4)) ⇒ ((1 2 3) (3 4)) (-partition-all-in-steps 3 2 '(1 2 3 4 5)) ⇒ ((1 2 3) (3 4 5) (5))
-- Function: -partition-by (fn list) Apply FN to each item in LIST, splitting it each time FN returns a new value.
(-partition-by 'even? ()) ⇒ () (-partition-by 'even? '(1 1 2 2 2 3 4 6 8)) ⇒ ((1 1) (2 2 2) (3) (4 6 8)) (--partition-by (< it 3) '(1 2 3 4 3 2 1)) ⇒ ((1 2) (3 4 3) (2 1))
-- Function: -partition-by-header (fn list) Apply FN to the first item in LIST. That is the header value. Apply FN to each item in LIST, splitting it each time FN returns the header value, but only after seeing at least one other value (the body).
(--partition-by-header (= it 1) '(1 2 3 1 2 1 2 3 4)) ⇒ ((1 2 3) (1 2) (1 2 3 4)) (--partition-by-header (> it 0) '(1 2 0 1 0 1 2 3 0)) ⇒ ((1 2 0) (1 0) (1 2 3 0)) (-partition-by-header 'even? '(2 1 1 1 4 1 3 5 6 6 1)) ⇒ ((2 1 1 1) (4 1 3 5) (6 6 1))
-- Function: -partition-after-pred (pred list) Partition directly after each time PRED is true on an element of LIST.
(-partition-after-pred #'booleanp ()) ⇒ () (-partition-after-pred #'booleanp '(t t)) ⇒ ((t) (t)) (-partition-after-pred #'booleanp '(0 0 t t 0 t)) ⇒ ((0 0 t) (t) (0 t))
-- Function: -partition-before-pred (pred list) Partition directly before each time PRED is true on an element of LIST.
(-partition-before-pred #'booleanp ()) ⇒ () (-partition-before-pred #'booleanp '(0 t)) ⇒ ((0) (t)) (-partition-before-pred #'booleanp '(0 0 t 0 t t)) ⇒ ((0 0) (t 0) (t) (t))
-- Function: -partition-before-item (item list) Partition directly before each time ITEM appears in LIST.
(-partition-before-item 3 ()) ⇒ () (-partition-before-item 3 '(1)) ⇒ ((1)) (-partition-before-item 3 '(3)) ⇒ ((3))
-- Function: -partition-after-item (item list) Partition directly after each time ITEM appears in LIST.
(-partition-after-item 3 ()) ⇒ () (-partition-after-item 3 '(1)) ⇒ ((1)) (-partition-after-item 3 '(3)) ⇒ ((3))
-- Function: -group-by (fn list) Separate LIST into an alist whose keys are FN applied to the elements of LIST. Keys are compared by ‘equal’.
(-group-by 'even? ()) ⇒ () (-group-by 'even? '(1 1 2 2 2 3 4 6 8)) ⇒ ((nil 1 1 3) (t 2 2 2 4 6 8)) (--group-by (car (split-string it "/")) '("a/b" "c/d" "a/e")) ⇒ (("a" "a/b" "a/e") ("c" "c/d"))
File: dash.info, Node: Indexing, Next: Set operations, Prev: Partitioning, Up: Functions
2.8 Indexing============
Functions retrieving or sorting based on list indices and relatedpredicates.
-- Function: -elem-index (elem list) Return the index of the first element in the given LIST which is equal to the query element ELEM, or nil if there is no such element.
(-elem-index 2 '(6 7 8 2 3 4)) ⇒ 3 (-elem-index "bar" '("foo" "bar" "baz")) ⇒ 1 (-elem-index '(1 2) '((3) (5 6) (1 2) nil)) ⇒ 2
-- Function: -elem-indices (elem list) Return the indices of all elements in LIST equal to the query element ELEM, in ascending order.
(-elem-indices 2 '(6 7 8 2 3 4 2 1)) ⇒ (3 6) (-elem-indices "bar" '("foo" "bar" "baz")) ⇒ (1) (-elem-indices '(1 2) '((3) (1 2) (5 6) (1 2) nil)) ⇒ (1 3)
-- Function: -find-index (pred list) Take a predicate PRED and a LIST and return the index of the first element in the list satisfying the predicate, or nil if there is no such element.
See also ‘-first’ (*note -first::).
(-find-index 'even? '(2 4 1 6 3 3 5 8)) ⇒ 0 (--find-index (< 5 it) '(2 4 1 6 3 3 5 8)) ⇒ 3 (-find-index (-partial 'string-lessp "baz") '("bar" "foo" "baz")) ⇒ 1
-- Function: -find-last-index (pred list) Take a predicate PRED and a LIST and return the index of the last element in the list satisfying the predicate, or nil if there is no such element.
See also ‘-last’ (*note -last::).
(-find-last-index 'even? '(2 4 1 6 3 3 5 8)) ⇒ 7 (--find-last-index (< 5 it) '(2 7 1 6 3 8 5 2)) ⇒ 5 (-find-last-index (-partial 'string-lessp "baz") '("q" "foo" "baz")) ⇒ 1
-- Function: -find-indices (pred list) Return the indices of all elements in LIST satisfying the predicate PRED, in ascending order.
(-find-indices 'even? '(2 4 1 6 3 3 5 8)) ⇒ (0 1 3 7) (--find-indices (< 5 it) '(2 4 1 6 3 3 5 8)) ⇒ (3 7) (-find-indices (-partial 'string-lessp "baz") '("bar" "foo" "baz")) ⇒ (1)
-- Function: -grade-up (comparator list) Grade elements of LIST using COMPARATOR relation. This yields a permutation vector such that applying this permutation to LIST sorts it in ascending order.
(-grade-up #'< '(3 1 4 2 1 3 3)) ⇒ (1 4 3 0 5 6 2) (let ((l '(3 1 4 2 1 3 3))) (-select-by-indices (-grade-up #'< l) l)) ⇒ (1 1 2 3 3 3 4)
-- Function: -grade-down (comparator list) Grade elements of LIST using COMPARATOR relation. This yields a permutation vector such that applying this permutation to LIST sorts it in descending order.
(-grade-down #'< '(3 1 4 2 1 3 3)) ⇒ (2 0 5 6 3 1 4) (let ((l '(3 1 4 2 1 3 3))) (-select-by-indices (-grade-down #'< l) l)) ⇒ (4 3 3 3 2 1 1)
File: dash.info, Node: Set operations, Next: Other list operations, Prev: Indexing, Up: Functions
2.9 Set operations==================
Operations pretending lists are sets.
-- Function: -union (list list2) Return a new list containing the elements of LIST and elements of LIST2 that are not in LIST. The test for equality is done with ‘equal’, or with ‘-compare-fn’ if that’s non-nil.
(-union '(1 2 3) '(3 4 5)) ⇒ (1 2 3 4 5) (-union '(1 2 3 4) ()) ⇒ (1 2 3 4) (-union '(1 1 2 2) '(3 2 1)) ⇒ (1 1 2 2 3)
-- Function: -difference (list list2) Return a new list with only the members of LIST that are not in LIST2. The test for equality is done with ‘equal’, or with ‘-compare-fn’ if that’s non-nil.
(-difference () ()) ⇒ () (-difference '(1 2 3) '(4 5 6)) ⇒ (1 2 3) (-difference '(1 2 3 4) '(3 4 5 6)) ⇒ (1 2)
-- Function: -intersection (list list2) Return a new list containing only the elements that are members of both LIST and LIST2. The test for equality is done with ‘equal’, or with ‘-compare-fn’ if that’s non-nil.
(-intersection () ()) ⇒ () (-intersection '(1 2 3) '(4 5 6)) ⇒ () (-intersection '(1 2 3 4) '(3 4 5 6)) ⇒ (3 4)
-- Function: -powerset (list) Return the power set of LIST.
(-powerset ()) ⇒ (nil) (-powerset '(x y z)) ⇒ ((x y z) (x y) (x z) (x) (y z) (y) (z) nil)
-- Function: -permutations (list) Return the permutations of LIST.
(-permutations ()) ⇒ (nil) (-permutations '(1 2)) ⇒ ((1 2) (2 1)) (-permutations '(a b c)) ⇒ ((a b c) (a c b) (b a c) (b c a) (c a b) (c b a))
-- Function: -distinct (list) Return a new list with all duplicates removed. The test for equality is done with ‘equal’, or with ‘-compare-fn’ if that’s non-nil.
Alias: ‘-uniq’
(-distinct ()) ⇒ () (-distinct '(1 2 2 4)) ⇒ (1 2 4) (-distinct '(t t t)) ⇒ (t)
File: dash.info, Node: Other list operations, Next: Tree operations, Prev: Set operations, Up: Functions
2.10 Other list operations==========================
Other list functions not fit to be classified elsewhere.
-- Function: -rotate (n list) Rotate LIST N places to the right. With N negative, rotate to the left. The time complexity is O(n).
(-rotate 3 '(1 2 3 4 5 6 7)) ⇒ (5 6 7 1 2 3 4) (-rotate -3 '(1 2 3 4 5 6 7)) ⇒ (4 5 6 7 1 2 3) (-rotate 16 '(1 2 3 4 5 6 7)) ⇒ (6 7 1 2 3 4 5)
-- Function: -repeat (n x) Return a new list of length N with each element being X. Return nil if N is less than 1.
(-repeat 3 :a) ⇒ (:a :a :a) (-repeat 1 :a) ⇒ (:a) (-repeat 0 :a) ⇒ nil
-- Function: -cons* (&rest args) Make a new list from the elements of ARGS. The last 2 elements of ARGS are used as the final cons of the result, so if the final element of ARGS is not a list, the result is a dotted list. With no ARGS, return nil.
(-cons* 1 2) ⇒ (1 . 2) (-cons* 1 2 3) ⇒ (1 2 . 3) (-cons* 1) ⇒ 1
-- Function: -snoc (list elem &rest elements) Append ELEM to the end of the list.
This is like ‘cons’, but operates on the end of list.
If ELEMENTS is non nil, append these to the list as well.
(-snoc '(1 2 3) 4) ⇒ (1 2 3 4) (-snoc '(1 2 3) 4 5 6) ⇒ (1 2 3 4 5 6) (-snoc '(1 2 3) '(4 5 6)) ⇒ (1 2 3 (4 5 6))
-- Function: -interpose (sep list) Return a new list of all elements in LIST separated by SEP.
(-interpose "-" ()) ⇒ () (-interpose "-" '("a")) ⇒ ("a") (-interpose "-" '("a" "b" "c")) ⇒ ("a" "-" "b" "-" "c")
-- Function: -interleave (&rest lists) Return a new list of the first item in each list, then the second etc.
(-interleave '(1 2) '("a" "b")) ⇒ (1 "a" 2 "b") (-interleave '(1 2) '("a" "b") '("A" "B")) ⇒ (1 "a" "A" 2 "b" "B") (-interleave '(1 2 3) '("a" "b")) ⇒ (1 "a" 2 "b")
-- Function: -iota (count &optional start step) Return a list containing COUNT numbers. Starts from START and adds STEP each time. The default START is zero, the default STEP is 1. This function takes its name from the corresponding primitive in the APL language.
(-iota 6) ⇒ (0 1 2 3 4 5) (-iota 4 2.5 -2) ⇒ (2.5 0.5 -1.5 -3.5) (-iota -1) error→ Wrong type argument: natnump, -1
-- Function: -zip-with (fn list1 list2) Zip the two lists LIST1 and LIST2 using a function FN. This function is applied pairwise taking as first argument element of LIST1 and as second argument element of LIST2 at corresponding position.
The anaphoric form ‘--zip-with’ binds the elements from LIST1 as symbol ‘it’, and the elements from LIST2 as symbol ‘other’.
(-zip-with '+ '(1 2 3) '(4 5 6)) ⇒ (5 7 9) (-zip-with 'cons '(1 2 3) '(4 5 6)) ⇒ ((1 . 4) (2 . 5) (3 . 6)) (--zip-with (concat it " and " other) '("Batman" "Jekyll") '("Robin" "Hyde")) ⇒ ("Batman and Robin" "Jekyll and Hyde")
-- Function: -zip (&rest lists) Zip LISTS together. Group the head of each list, followed by the second elements of each list, and so on. The lengths of the returned groupings are equal to the length of the shortest input list.
If two lists are provided as arguments, return the groupings as a list of cons cells. Otherwise, return the groupings as a list of lists.
Use ‘-zip-lists’ (*note -zip-lists::) if you need the return value to always be a list of lists.
Alias: ‘-zip-pair’
See also: ‘-zip-lists’ (*note -zip-lists::)
(-zip '(1 2 3) '(4 5 6)) ⇒ ((1 . 4) (2 . 5) (3 . 6)) (-zip '(1 2 3) '(4 5 6 7)) ⇒ ((1 . 4) (2 . 5) (3 . 6)) (-zip '(1 2) '(3 4 5) '(6)) ⇒ ((1 3 6))
-- Function: -zip-lists (&rest lists) Zip LISTS together. Group the head of each list, followed by the second elements of each list, and so on. The lengths of the returned groupings are equal to the length of the shortest input list.
The return value is always list of lists, which is a difference from ‘-zip-pair’ which returns a cons-cell in case two input lists are provided.
See also: ‘-zip’ (*note -zip::)
(-zip-lists '(1 2 3) '(4 5 6)) ⇒ ((1 4) (2 5) (3 6)) (-zip-lists '(1 2 3) '(4 5 6 7)) ⇒ ((1 4) (2 5) (3 6)) (-zip-lists '(1 2) '(3 4 5) '(6)) ⇒ ((1 3 6))
-- Function: -zip-fill (fill-value &rest lists) Zip LISTS, with FILL-VALUE padded onto the shorter lists. The lengths of the returned groupings are equal to the length of the longest input list.
(-zip-fill 0 '(1 2 3 4 5) '(6 7 8 9)) ⇒ ((1 . 6) (2 . 7) (3 . 8) (4 . 9) (5 . 0))
-- Function: -unzip (lists) Unzip LISTS.
This works just like ‘-zip’ (*note -zip::) but takes a list of lists instead of a variable number of arguments, such that
(-unzip (-zip L1 L2 L3 ...))
is identity (given that the lists are the same length).
Note in particular that calling this on a list of two lists will return a list of cons-cells such that the above identity works.
See also: ‘-zip’ (*note -zip::)
(-unzip (-zip '(1 2 3) '(a b c) '("e" "f" "g"))) ⇒ ((1 2 3) (a b c) ("e" "f" "g")) (-unzip '((1 2) (3 4) (5 6) (7 8) (9 10))) ⇒ ((1 3 5 7 9) (2 4 6 8 10)) (-unzip '((1 2) (3 4))) ⇒ ((1 . 3) (2 . 4))
-- Function: -cycle (list) Return an infinite circular copy of LIST. The returned list cycles through the elements of LIST and repeats from the beginning.
(-take 5 (-cycle '(1 2 3))) ⇒ (1 2 3 1 2) (-take 7 (-cycle '(1 "and" 3))) ⇒ (1 "and" 3 1 "and" 3 1) (-zip (-cycle '(1 2 3)) '(1 2)) ⇒ ((1 . 1) (2 . 2))
-- Function: -pad (fill-value &rest lists) Appends FILL-VALUE to the end of each list in LISTS such that they will all have the same length.
(-pad 0 ()) ⇒ (nil) (-pad 0 '(1)) ⇒ ((1)) (-pad 0 '(1 2 3) '(4 5)) ⇒ ((1 2 3) (4 5 0))
-- Function: -table (fn &rest lists) Compute outer product of LISTS using function FN.
The function FN should have the same arity as the number of supplied lists.
The outer product is computed by applying fn to all possible combinations created by taking one element from each list in order. The dimension of the result is (length lists).
See also: ‘-table-flat’ (*note -table-flat::)
(-table '* '(1 2 3) '(1 2 3)) ⇒ ((1 2 3) (2 4 6) (3 6 9)) (-table (lambda (a b) (-sum (-zip-with '* a b))) '((1 2) (3 4)) '((1 3) (2 4))) ⇒ ((7 15) (10 22)) (apply '-table 'list (-repeat 3 '(1 2))) ⇒ ((((1 1 1) (2 1 1)) ((1 2 1) (2 2 1))) (((1 1 2) (2 1 2)) ((1 2 2) (2 2 2))))
-- Function: -table-flat (fn &rest lists) Compute flat outer product of LISTS using function FN.
The function FN should have the same arity as the number of supplied lists.
The outer product is computed by applying fn to all possible combinations created by taking one element from each list in order. The results are flattened, ignoring the tensor structure of the result. This is equivalent to calling:
(-flatten-n (1- (length lists)) (apply ’-table fn lists))
but the implementation here is much more efficient.
See also: ‘-flatten-n’ (*note -flatten-n::), ‘-table’ (*note -table::)
(-table-flat 'list '(1 2 3) '(a b c)) ⇒ ((1 a) (2 a) (3 a) (1 b) (2 b) (3 b) (1 c) (2 c) (3 c)) (-table-flat '* '(1 2 3) '(1 2 3)) ⇒ (1 2 3 2 4 6 3 6 9) (apply '-table-flat 'list (-repeat 3 '(1 2))) ⇒ ((1 1 1) (2 1 1) (1 2 1) (2 2 1) (1 1 2) (2 1 2) (1 2 2) (2 2 2))
-- Function: -first (pred list) Return the first item in LIST for which PRED returns non-nil. Return nil if no such element is found. To get the first item in the list no questions asked, use ‘car’.
Alias: ‘-find’.
This function’s anaphoric counterpart is ‘--first’.
(-first #'natnump '(-1 0 1)) ⇒ 0 (-first #'null '(1 2 3)) ⇒ nil (--first (> it 2) '(1 2 3)) ⇒ 3
-- Function: -some (pred list) Return (PRED x) for the first LIST item where (PRED x) is non-nil, else nil.
Alias: ‘-any’.
This function’s anaphoric counterpart is ‘--some’.
(-some (lambda (s) (string-match-p "x" s)) '("foo" "axe" "xor")) ⇒ 1 (-some (lambda (s) (string-match-p "x" s)) '("foo" "bar" "baz")) ⇒ nil (--some (member 'foo it) '((foo bar) (baz))) ⇒ (foo bar)
-- Function: -last (pred list) Return the last x in LIST where (PRED x) is non-nil, else nil.
(-last 'even? '(1 2 3 4 5 6 3 3 3)) ⇒ 6 (-last 'even? '(1 3 7 5 9)) ⇒ nil (--last (> (length it) 3) '("a" "looong" "word" "and" "short" "one")) ⇒ "short"
-- Function: -first-item (list) Return the first item of LIST, or nil on an empty list.
See also: ‘-second-item’ (*note -second-item::), ‘-last-item’ (*note -last-item::).
(-first-item '(1 2 3)) ⇒ 1 (-first-item nil) ⇒ nil (let ((list (list 1 2 3))) (setf (-first-item list) 5) list) ⇒ (5 2 3)
-- Function: -second-item (list) Return the second item of LIST, or nil if LIST is too short.
See also: ‘-third-item’ (*note -third-item::).
(-second-item '(1 2 3)) ⇒ 2 (-second-item nil) ⇒ nil
-- Function: -third-item (list) Return the third item of LIST, or nil if LIST is too short.
See also: ‘-fourth-item’ (*note -fourth-item::).
(-third-item '(1 2 3)) ⇒ 3 (-third-item nil) ⇒ nil
-- Function: -fourth-item (list) Return the fourth item of LIST, or nil if LIST is too short.
See also: ‘-fifth-item’ (*note -fifth-item::).
(-fourth-item '(1 2 3 4)) ⇒ 4 (-fourth-item nil) ⇒ nil
-- Function: -fifth-item (list) Return the fifth item of LIST, or nil if LIST is too short.
See also: ‘-last-item’ (*note -last-item::).
(-fifth-item '(1 2 3 4 5)) ⇒ 5 (-fifth-item nil) ⇒ nil
-- Function: -last-item (list) Return the last item of LIST, or nil on an empty list.
(-last-item '(1 2 3)) ⇒ 3 (-last-item nil) ⇒ nil (let ((list (list 1 2 3))) (setf (-last-item list) 5) list) ⇒ (1 2 5)
-- Function: -butlast (list) Return a list of all items in list except for the last.
(-butlast '(1 2 3)) ⇒ (1 2) (-butlast '(1 2)) ⇒ (1) (-butlast '(1)) ⇒ nil
-- Function: -sort (comparator list) Sort LIST, stably, comparing elements using COMPARATOR. Return the sorted list. LIST is NOT modified by side effects. COMPARATOR is called with two elements of LIST, and should return non-nil if the first element should sort before the second.
(-sort '< '(3 1 2)) ⇒ (1 2 3) (-sort '> '(3 1 2)) ⇒ (3 2 1) (--sort (< it other) '(3 1 2)) ⇒ (1 2 3)
-- Function: -list (arg) Ensure ARG is a list. If ARG is already a list, return it as is (not a copy). Otherwise, return a new list with ARG as its only element.
Another supported calling convention is (-list &rest ARGS). In this case, if ARG is not a list, a new list with all of ARGS as elements is returned. This use is supported for backward compatibility and is otherwise deprecated.
(-list 1) ⇒ (1) (-list ()) ⇒ () (-list '(1 2 3)) ⇒ (1 2 3)
-- Function: -fix (fn list) Compute the (least) fixpoint of FN with initial input LIST.
FN is called at least once, results are compared with ‘equal’.
(-fix (lambda (l) (-non-nil (--mapcat (-split-at (/ (length it) 2) it) l))) '((1 2 3))) ⇒ ((1) (2) (3)) (let ((l '((starwars scifi) (jedi starwars warrior)))) (--fix (-uniq (--mapcat (cons it (cdr (assq it l))) it)) '(jedi book))) ⇒ (jedi starwars warrior scifi book)
File: dash.info, Node: Tree operations, Next: Threading macros, Prev: Other list operations, Up: Functions
2.11 Tree operations====================
Functions pretending lists are trees.
-- Function: -tree-seq (branch children tree) Return a sequence of the nodes in TREE, in depth-first search order.
BRANCH is a predicate of one argument that returns non-nil if the passed argument is a branch, that is, a node that can have children.
CHILDREN is a function of one argument that returns the children of the passed branch node.
Non-branch nodes are simply copied.
(-tree-seq 'listp 'identity '(1 (2 3) 4 (5 (6 7)))) ⇒ ((1 (2 3) 4 (5 (6 7))) 1 (2 3) 2 3 4 (5 (6 7)) 5 (6 7) 6 7) (-tree-seq 'listp 'reverse '(1 (2 3) 4 (5 (6 7)))) ⇒ ((1 (2 3) 4 (5 (6 7))) (5 (6 7)) (6 7) 7 6 5 4 (2 3) 3 2 1) (--tree-seq (vectorp it) (append it nil) [1 [2 3] 4 [5 [6 7]]]) ⇒ ([1 [2 3] 4 [5 [6 7]]] 1 [2 3] 2 3 4 [5 [6 7]] 5 [6 7] 6 7)
-- Function: -tree-map (fn tree) Apply FN to each element of TREE while preserving the tree structure.
(-tree-map '1+ '(1 (2 3) (4 (5 6) 7))) ⇒ (2 (3 4) (5 (6 7) 8)) (-tree-map '(lambda (x) (cons x (expt 2 x))) '(1 (2 3) 4)) ⇒ ((1 . 2) ((2 . 4) (3 . 8)) (4 . 16)) (--tree-map (length it) '("<body>" ("<p>" "text" "</p>") "</body>")) ⇒ (6 (3 4 4) 7)
-- Function: -tree-map-nodes (pred fun tree) Call FUN on each node of TREE that satisfies PRED.
If PRED returns nil, continue descending down this node. If PRED returns non-nil, apply FUN to this node and do not descend further.
(-tree-map-nodes 'vectorp (lambda (x) (-sum (append x nil))) '(1 [2 3] 4 (5 [6 7] 8))) ⇒ (1 5 4 (5 13 8)) (-tree-map-nodes 'keywordp (lambda (x) (symbol-name x)) '(1 :foo 4 ((5 6 :bar) :baz 8))) ⇒ (1 ":foo" 4 ((5 6 ":bar") ":baz" 8)) (--tree-map-nodes (eq (car-safe it) 'add-mode) (-concat it (list :mode 'emacs-lisp-mode)) '(with-mode emacs-lisp-mode (foo bar) (add-mode a b) (baz (add-mode c d)))) ⇒ (with-mode emacs-lisp-mode (foo bar) (add-mode a b :mode emacs-lisp-mode) (baz (add-mode c d :mode emacs-lisp-mode)))
-- Function: -tree-reduce (fn tree) Use FN to reduce elements of list TREE. If elements of TREE are lists themselves, apply the reduction recursively.
FN is first applied to first element of the list and second element, then on this result and third element from the list etc.
See ‘-reduce-r’ (*note -reduce-r::) for how exactly are lists of zero or one element handled.
(-tree-reduce '+ '(1 (2 3) (4 5))) ⇒ 15 (-tree-reduce 'concat '("strings" (" on" " various") ((" levels")))) ⇒ "strings on various levels" (--tree-reduce (cond ((stringp it) (concat it " " acc)) (t (let ((sn (symbol-name it))) (concat "<" sn ">" acc "</" sn ">")))) '(body (p "some words") (div "more" (b "bold") "words"))) ⇒ "<body><p>some words</p> <div>more <b>bold</b> words</div></body>"
-- Function: -tree-reduce-from (fn init-value tree) Use FN to reduce elements of list TREE. If elements of TREE are lists themselves, apply the reduction recursively.
FN is first applied to INIT-VALUE and first element of the list, then on this result and second element from the list etc.
The initial value is ignored on cons pairs as they always contain two elements.
(-tree-reduce-from '+ 1 '(1 (1 1) ((1)))) ⇒ 8 (--tree-reduce-from (-concat acc (list it)) nil '(1 (2 3 (4 5)) (6 7))) ⇒ ((7 6) ((5 4) 3 2) 1)
-- Function: -tree-mapreduce (fn folder tree) Apply FN to each element of TREE, and make a list of the results. If elements of TREE are lists themselves, apply FN recursively to elements of these nested lists.
Then reduce the resulting lists using FOLDER and initial value INIT-VALUE. See ‘-reduce-r-from’ (*note -reduce-r-from::).
This is the same as calling ‘-tree-reduce’ (*note -tree-reduce::) after ‘-tree-map’ (*note -tree-map::) but is twice as fast as it only traverse the structure once.
(-tree-mapreduce 'list 'append '(1 (2 (3 4) (5 6)) (7 (8 9)))) ⇒ (1 2 3 4 5 6 7 8 9) (--tree-mapreduce 1 (+ it acc) '(1 (2 (4 9) (2 1)) (7 (4 3)))) ⇒ 9 (--tree-mapreduce 0 (max acc (1+ it)) '(1 (2 (4 9) (2 1)) (7 (4 3)))) ⇒ 3
-- Function: -tree-mapreduce-from (fn folder init-value tree) Apply FN to each element of TREE, and make a list of the results. If elements of TREE are lists themselves, apply FN recursively to elements of these nested lists.
Then reduce the resulting lists using FOLDER and initial value INIT-VALUE. See ‘-reduce-r-from’ (*note -reduce-r-from::).
This is the same as calling ‘-tree-reduce-from’ (*note -tree-reduce-from::) after ‘-tree-map’ (*note -tree-map::) but is twice as fast as it only traverse the structure once.
(-tree-mapreduce-from 'identity '* 1 '(1 (2 (3 4) (5 6)) (7 (8 9)))) ⇒ 362880 (--tree-mapreduce-from (+ it it) (cons it acc) nil '(1 (2 (4 9) (2 1)) (7 (4 3)))) ⇒ (2 (4 (8 18) (4 2)) (14 (8 6))) (concat "{" (--tree-mapreduce-from (cond ((-cons-pair? it) (concat (symbol-name (car it)) " -> " (symbol-name (cdr it)))) (t (concat (symbol-name it) " : {"))) (concat it (unless (or (equal acc "}") (equal (substring it (1- (length it))) "{")) ", ") acc) "}" '((elisp-mode (foo (bar . booze)) (baz . qux)) (c-mode (foo . bla) (bum . bam))))) ⇒ "{elisp-mode : {foo : {bar -> booze}, baz -> qux}, c-mode : {foo -> bla, bum -> bam}}"
-- Function: -clone (list) Create a deep copy of LIST. The new list has the same elements and structure but all cons are replaced with new ones. This is useful when you need to clone a structure such as plist or alist.
(let* ((a '(1 2 3)) (b (-clone a))) (nreverse a) b) ⇒ (1 2 3)
File: dash.info, Node: Threading macros, Next: Binding, Prev: Tree operations, Up: Functions
2.12 Threading macros=====================
Macros that conditionally combine sequential forms for brevity orreadability.
-- Macro: -> (x &optional form &rest more) Thread the expr through the forms. Insert X as the second item in the first form, making a list of it if it is not a list already. If there are more forms, insert the first form as the second item in second form, etc.
(-> '(2 3 5)) ⇒ (2 3 5) (-> '(2 3 5) (append '(8 13))) ⇒ (2 3 5 8 13) (-> '(2 3 5) (append '(8 13)) (-slice 1 -1)) ⇒ (3 5 8)
-- Macro: ->> (x &optional form &rest more) Thread the expr through the forms. Insert X as the last item in the first form, making a list of it if it is not a list already. If there are more forms, insert the first form as the last item in second form, etc.
(->> '(1 2 3) (-map 'square)) ⇒ (1 4 9) (->> '(1 2 3) (-map 'square) (-remove 'even?)) ⇒ (1 9) (->> '(1 2 3) (-map 'square) (-reduce '+)) ⇒ 14
-- Macro: --> (x &rest forms) Starting with the value of X, thread each expression through FORMS.
Insert X at the position signified by the symbol ‘it’ in the first form. If there are more forms, insert the first form at the position signified by ‘it’ in in second form, etc.
(--> "def" (concat "abc" it "ghi")) ⇒ "abcdefghi" (--> "def" (concat "abc" it "ghi") (upcase it)) ⇒ "ABCDEFGHI" (--> "def" (concat "abc" it "ghi") upcase) ⇒ "ABCDEFGHI"
-- Macro: -as-> (value variable &rest forms) Starting with VALUE, thread VARIABLE through FORMS.
In the first form, bind VARIABLE to VALUE. In the second form, bind VARIABLE to the result of the first form, and so forth.
(-as-> 3 my-var (1+ my-var) (list my-var) (mapcar (lambda (ele) (* 2 ele)) my-var)) ⇒ (8) (-as-> 3 my-var 1+) ⇒ 4 (-as-> 3 my-var) ⇒ 3
-- Macro: -some-> (x &optional form &rest more) When expr is non-nil, thread it through the first form (via ‘->’ (*note ->::)), and when that result is non-nil, through the next form, etc.
(-some-> '(2 3 5)) ⇒ (2 3 5) (-some-> 5 square) ⇒ 25 (-some-> 5 even? square) ⇒ nil
-- Macro: -some->> (x &optional form &rest more) When expr is non-nil, thread it through the first form (via ‘->>’ (*note ->>::)), and when that result is non-nil, through the next form, etc.
(-some->> '(1 2 3) (-map 'square)) ⇒ (1 4 9) (-some->> '(1 3 5) (-last 'even?) (+ 100)) ⇒ nil (-some->> '(2 4 6) (-last 'even?) (+ 100)) ⇒ 106
-- Macro: -some--> (expr &rest forms) Thread EXPR through FORMS via ‘-->’ (*note -->::), while the result is non-nil. When EXPR evaluates to non-nil, thread the result through the first of FORMS, and when that result is non-nil, thread it through the next form, etc.
(-some--> "def" (concat "abc" it "ghi")) ⇒ "abcdefghi" (-some--> nil (concat "abc" it "ghi")) ⇒ nil (-some--> '(0 1) (-remove #'natnump it) (append it it) (-map #'1+ it)) ⇒ ()
-- Macro: -doto (init &rest forms) Evaluate INIT and pass it as argument to FORMS with ‘->’ (*note ->::). The RESULT of evaluating INIT is threaded through each of FORMS individually using ‘->’ (*note ->::), which see. The return value is RESULT, which FORMS may have modified by side effect.
(-doto (list 1 2 3) pop pop) ⇒ (3) (-doto (cons 1 2) (setcar 3) (setcdr 4)) ⇒ (3 . 4) (gethash 'k (--doto (make-hash-table) (puthash 'k 'v it))) ⇒ v
File: dash.info, Node: Binding, Next: Side effects, Prev: Threading macros, Up: Functions
2.13 Binding============
Macros that combine ‘let’ and ‘let*’ with destructuring and flowcontrol.
-- Macro: -when-let ((var val) &rest body) If VAL evaluates to non-nil, bind it to VAR and execute body.
Note: binding is done according to ‘-let’ (*note -let::).
(-when-let (match-index (string-match "d" "abcd")) (+ match-index 2)) ⇒ 5 (-when-let ((&plist :foo foo) (list :foo "foo")) foo) ⇒ "foo" (-when-let ((&plist :foo foo) (list :bar "bar")) foo) ⇒ nil
-- Macro: -when-let* (vars-vals &rest body) If all VALS evaluate to true, bind them to their corresponding VARS and execute body. VARS-VALS should be a list of (VAR VAL) pairs.
Note: binding is done according to ‘-let*’ (*note -let*::). VALS are evaluated sequentially, and evaluation stops after the first nil VAL is encountered.
(-when-let* ((x 5) (y 3) (z (+ y 4))) (+ x y z)) ⇒ 15 (-when-let* ((x 5) (y nil) (z 7)) (+ x y z)) ⇒ nil
-- Macro: -if-let ((var val) then &rest else) If VAL evaluates to non-nil, bind it to VAR and do THEN, otherwise do ELSE.
Note: binding is done according to ‘-let’ (*note -let::).
(-if-let (match-index (string-match "d" "abc")) (+ match-index 3) 7) ⇒ 7 (--if-let (even? 4) it nil) ⇒ t
-- Macro: -if-let* (vars-vals then &rest else) If all VALS evaluate to true, bind them to their corresponding VARS and do THEN, otherwise do ELSE. VARS-VALS should be a list of (VAR VAL) pairs.
Note: binding is done according to ‘-let*’ (*note -let*::). VALS are evaluated sequentially, and evaluation stops after the first nil VAL is encountered.
(-if-let* ((x 5) (y 3) (z 7)) (+ x y z) "foo") ⇒ 15 (-if-let* ((x 5) (y nil) (z 7)) (+ x y z) "foo") ⇒ "foo" (-if-let* (((_ _ x) '(nil nil 7))) x) ⇒ 7
-- Macro: -let (varlist &rest body) Bind variables according to VARLIST then eval BODY.
VARLIST is a list of lists of the form (PATTERN SOURCE). Each PATTERN is matched against the SOURCE "structurally". SOURCE is only evaluated once for each PATTERN. Each PATTERN is matched recursively, and can therefore contain sub-patterns which are matched against corresponding sub-expressions of SOURCE.
All the SOURCEs are evalled before any symbols are bound (i.e. "in parallel").
If VARLIST only contains one (PATTERN SOURCE) element, you can optionally specify it using a vector and discarding the outer-most parens. Thus
(-let ((PATTERN SOURCE)) ...)
becomes
(-let [PATTERN SOURCE] ...).
‘-let’ (*note -let::) uses a convention of not binding places (symbols) starting with _ whenever it’s possible. You can use this to skip over entries you don’t care about. However, this is not *always* possible (as a result of implementation) and these symbols might get bound to undefined values.
Following is the overview of supported patterns. Remember that patterns can be matched recursively, so every a, b, aK in the following can be a matching construct and not necessarily a symbol/variable.
Symbol:
a - bind the SOURCE to A. This is just like regular ‘let’.
Conses and lists:
(a) - bind ‘car’ of cons/list to A
(a . b) - bind car of cons to A and ‘cdr’ to B
(a b) - bind car of list to A and ‘cadr’ to B
(a1 a2 a3 ...) - bind 0th car of list to A1, 1st to A2, 2nd to A3...
(a1 a2 a3 ... aN . rest) - as above, but bind the Nth cdr to REST.
Vectors:
[a] - bind 0th element of a non-list sequence to A (works with vectors, strings, bit arrays...)
[a1 a2 a3 ...] - bind 0th element of non-list sequence to A0, 1st to A1, 2nd to A2, ... If the PATTERN is shorter than SOURCE, the values at places not in PATTERN are ignored. If the PATTERN is longer than SOURCE, an ‘error’ is thrown.
[a1 a2 a3 ... &rest rest] - as above, but bind the rest of the sequence to REST. This is conceptually the same as improper list matching (a1 a2 ... aN . rest)
Key/value stores:
(&plist key0 a0 ... keyN aN) - bind value mapped by keyK in the SOURCE plist to aK. If the value is not found, aK is nil. Uses ‘plist-get’ to fetch values.
(&alist key0 a0 ... keyN aN) - bind value mapped by keyK in the SOURCE alist to aK. If the value is not found, aK is nil. Uses ‘assoc’ to fetch values.
(&hash key0 a0 ... keyN aN) - bind value mapped by keyK in the SOURCE hash table to aK. If the value is not found, aK is nil. Uses ‘gethash’ to fetch values.
Further, special keyword &keys supports "inline" matching of plist-like key-value pairs, similarly to &keys keyword of ‘cl-defun’.
(a1 a2 ... aN &keys key1 b1 ... keyN bK)
This binds N values from the list to a1 ... aN, then interprets the cdr as a plist (see key/value matching above).
A shorthand notation for kv-destructuring exists which allows the patterns be optionally left out and derived from the key name in the following fashion:
- a key :foo is converted into ‘foo’ pattern, - a key ’bar is converted into ‘bar’ pattern, - a key "baz" is converted into ‘baz’ pattern.
That is, the entire value under the key is bound to the derived variable without any further destructuring.
This is possible only when the form following the key is not a valid pattern (i.e. not a symbol, a cons cell or a vector). Otherwise the matching proceeds as usual and in case of an invalid spec fails with an error.
Thus the patterns are normalized as follows:
;; derive all the missing patterns (&plist :foo ’bar "baz") => (&plist :foo foo ’bar bar "baz" baz)
;; we can specify some but not others (&plist :foo ’bar explicit-bar) => (&plist :foo foo ’bar explicit-bar)
;; nothing happens, we store :foo in x (&plist :foo x) => (&plist :foo x)
;; nothing happens, we match recursively (&plist :foo (a b c)) => (&plist :foo (a b c))
You can name the source using the syntax SYMBOL &as PATTERN. This syntax works with lists (proper or improper), vectors and all types of maps.
(list &as a b c) (list 1 2 3)
binds A to 1, B to 2, C to 3 and LIST to (1 2 3).
Similarly:
(bounds &as beg . end) (cons 1 2)
binds BEG to 1, END to 2 and BOUNDS to (1 . 2).
(items &as first . rest) (list 1 2 3)
binds FIRST to 1, REST to (2 3) and ITEMS to (1 2 3)
[vect &as _ b c] [1 2 3]
binds B to 2, C to 3 and VECT to [1 2 3] (_ avoids binding as usual).
(plist &as &plist :b b) (list :a 1 :b 2 :c 3)
binds B to 2 and PLIST to (:a 1 :b 2 :c 3). Same for &alist and &hash.
This is especially useful when we want to capture the result of a computation and destructure at the same time. Consider the form (function-returning-complex-structure) returning a list of two vectors with two items each. We want to capture this entire result and pass it to another computation, but at the same time we want to get the second item from each vector. We can achieve it with pattern
(result &as [_ a] [_ b]) (function-returning-complex-structure)
Note: Clojure programmers may know this feature as the ":as binding". The difference is that we put the &as at the front because we need to support improper list binding.
(-let (([a (b c) d] [1 (2 3) 4])) (list a b c d)) ⇒ (1 2 3 4) (-let [(a b c . d) (list 1 2 3 4 5 6)] (list a b c d)) ⇒ (1 2 3 (4 5 6)) (-let [(&plist :foo foo :bar bar) (list :baz 3 :foo 1 :qux 4 :bar 2)] (list foo bar)) ⇒ (1 2)
-- Macro: -let* (varlist &rest body) Bind variables according to VARLIST then eval BODY.
VARLIST is a list of lists of the form (PATTERN SOURCE). Each PATTERN is matched against the SOURCE structurally. SOURCE is only evaluated once for each PATTERN.
Each SOURCE can refer to the symbols already bound by this VARLIST. This is useful if you want to destructure SOURCE recursively but also want to name the intermediate structures.
See ‘-let’ (*note -let::) for the list of all possible patterns.
(-let* (((a . b) (cons 1 2)) ((c . d) (cons 3 4))) (list a b c d)) ⇒ (1 2 3 4) (-let* (((a . b) (cons 1 (cons 2 3))) ((c . d) b)) (list a b c d)) ⇒ (1 (2 . 3) 2 3) (-let* (((&alist "foo" foo "bar" bar) (list (cons "foo" 1) (cons "bar" (list 'a 'b 'c)))) ((a b c) bar)) (list foo a b c bar)) ⇒ (1 a b c (a b c))
-- Macro: -lambda (match-form &rest body) Return a lambda which destructures its input as MATCH-FORM and executes BODY.
Note that you have to enclose the MATCH-FORM in a pair of parens, such that:
(-lambda (x) body) (-lambda (x y ...) body)
has the usual semantics of ‘lambda’. Furthermore, these get translated into normal ‘lambda’, so there is no performance penalty.
See ‘-let’ (*note -let::) for a description of the destructuring mechanism.
(-map (-lambda ((x y)) (+ x y)) '((1 2) (3 4) (5 6))) ⇒ (3 7 11) (-map (-lambda ([x y]) (+ x y)) '([1 2] [3 4] [5 6])) ⇒ (3 7 11) (funcall (-lambda ((_ . a) (_ . b)) (-concat a b)) '(1 2 3) '(4 5 6)) ⇒ (2 3 5 6)
-- Macro: -setq ([match-form val] ...) Bind each MATCH-FORM to the value of its VAL.
MATCH-FORM destructuring is done according to the rules of ‘-let’ (*note -let::).
This macro allows you to bind multiple variables by destructuring the value, so for example:
(-setq (a b) x (&plist :c c) plist)
expands roughly speaking to the following code
(setq a (car x) b (cadr x) c (plist-get plist :c))
Care is taken to only evaluate each VAL once so that in case of multiple assignments it does not cause unexpected side effects.
(let (a) (-setq a 1) a) ⇒ 1 (let (a b) (-setq (a b) (list 1 2)) (list a b)) ⇒ (1 2) (let (c) (-setq (&plist :c c) (list :c "c")) c) ⇒ "c"
File: dash.info, Node: Side effects, Next: Destructive operations, Prev: Binding, Up: Functions
2.14 Side effects=================
Functions iterating over lists for side effect only.
-- Function: -each (list fn) Call FN on each element of LIST. Return nil; this function is intended for side effects.
Its anaphoric counterpart is ‘--each’.
For access to the current element’s index in LIST, see ‘-each-indexed’ (*note -each-indexed::).
(let (l) (-each '(1 2 3) (lambda (x) (push x l))) l) ⇒ (3 2 1) (let (l) (--each '(1 2 3) (push it l)) l) ⇒ (3 2 1) (-each '(1 2 3) #'identity) ⇒ nil
-- Function: -each-while (list pred fn) Call FN on each ITEM in LIST, while (PRED ITEM) is non-nil. Once an ITEM is reached for which PRED returns nil, FN is no longer called. Return nil; this function is intended for side effects.
Its anaphoric counterpart is ‘--each-while’.
(let (l) (-each-while '(2 4 5 6) #'even? (lambda (x) (push x l))) l) ⇒ (4 2) (let (l) (--each-while '(1 2 3 4) (< it 3) (push it l)) l) ⇒ (2 1) (let ((s 0)) (--each-while '(1 3 4 5) (< it 5) (setq s (+ s it))) s) ⇒ 8
-- Function: -each-indexed (list fn) Call FN on each index and element of LIST. For each ITEM at INDEX in LIST, call (funcall FN INDEX ITEM). Return nil; this function is intended for side effects.
See also: ‘-map-indexed’ (*note -map-indexed::).
(let (l) (-each-indexed '(a b c) (lambda (i x) (push (list x i) l))) l) ⇒ ((c 2) (b 1) (a 0)) (let (l) (--each-indexed '(a b c) (push (list it it-index) l)) l) ⇒ ((c 2) (b 1) (a 0)) (let (l) (--each-indexed () (push it l)) l) ⇒ ()
-- Function: -each-r (list fn) Call FN on each element of LIST in reversed order. Return nil; this function is intended for side effects.
Its anaphoric counterpart is ‘--each-r’.
(let (l) (-each-r '(1 2 3) (lambda (x) (push x l))) l) ⇒ (1 2 3) (let (l) (--each-r '(1 2 3) (push it l)) l) ⇒ (1 2 3) (-each-r '(1 2 3) #'identity) ⇒ nil
-- Function: -each-r-while (list pred fn) Call FN on each ITEM in reversed LIST, while (PRED ITEM) is non-nil. Once an ITEM is reached for which PRED returns nil, FN is no longer called. Return nil; this function is intended for side effects.
Its anaphoric counterpart is ‘--each-r-while’.
(let (l) (-each-r-while '(2 4 5 6) #'even? (lambda (x) (push x l))) l) ⇒ (6) (let (l) (--each-r-while '(1 2 3 4) (>= it 3) (push it l)) l) ⇒ (3 4) (let ((s 0)) (--each-r-while '(1 2 3 5) (> it 1) (setq s (+ s it))) s) ⇒ 10
-- Function: -dotimes (num fn) Call FN NUM times, presumably for side effects. FN is called with a single argument on successive integers running from 0, inclusive, to NUM, exclusive. FN is not called if NUM is less than 1.
This function’s anaphoric counterpart is ‘--dotimes’.
(let (s) (-dotimes 3 (lambda (n) (push n s))) s) ⇒ (2 1 0) (let (s) (-dotimes 0 (lambda (n) (push n s))) s) ⇒ () (let (s) (--dotimes 5 (push it s)) s) ⇒ (4 3 2 1 0)
File: dash.info, Node: Destructive operations, Next: Function combinators, Prev: Side effects, Up: Functions
2.15 Destructive operations===========================
Macros that modify variables holding lists.
-- Macro: !cons (car cdr) Destructive: Set CDR to the cons of CAR and CDR.
(let (l) (!cons 5 l) l) ⇒ (5) (let ((l '(3))) (!cons 5 l) l) ⇒ (5 3)
-- Macro: !cdr (list) Destructive: Set LIST to the cdr of LIST.
(let ((l '(3))) (!cdr l) l) ⇒ () (let ((l '(3 5))) (!cdr l) l) ⇒ (5)
File: dash.info, Node: Function combinators, Prev: Destructive operations, Up: Functions
2.16 Function combinators=========================
Functions that manipulate and compose other functions.
-- Function: -partial (fn &rest args) Take a function FN and fewer than the normal arguments to FN, and return a fn that takes a variable number of additional ARGS. When called, the returned function calls FN with ARGS first and then additional args.
(funcall (-partial '- 5) 3) ⇒ 2 (funcall (-partial '+ 5 2) 3) ⇒ 10
-- Function: -rpartial (fn &rest args) Takes a function FN and fewer than the normal arguments to FN, and returns a fn that takes a variable number of additional ARGS. When called, the returned function calls FN with the additional args first and then ARGS.
(funcall (-rpartial '- 5) 8) ⇒ 3 (funcall (-rpartial '- 5 2) 10) ⇒ 3
-- Function: -juxt (&rest fns) Takes a list of functions and returns a fn that is the juxtaposition of those fns. The returned fn takes a variable number of args, and returns a list containing the result of applying each fn to the args (left-to-right).
(funcall (-juxt '+ '-) 3 5) ⇒ (8 -2) (-map (-juxt 'identity 'square) '(1 2 3)) ⇒ ((1 1) (2 4) (3 9))
-- Function: -compose (&rest fns) Takes a list of functions and returns a fn that is the composition of those fns. The returned fn takes a variable number of arguments, and returns the result of applying each fn to the result of applying the previous fn to the arguments (right-to-left).
(funcall (-compose 'square '+) 2 3) ⇒ (square (+ 2 3)) (funcall (-compose 'identity 'square) 3) ⇒ (square 3) (funcall (-compose 'square 'identity) 3) ⇒ (square 3)
-- Function: -applify (fn) Changes an n-arity function FN to a 1-arity function that expects a list with n items as arguments
(-map (-applify '+) '((1 1 1) (1 2 3) (5 5 5))) ⇒ (3 6 15) (-map (-applify (lambda (a b c) `(,a (,b (,c))))) '((1 1 1) (1 2 3) (5 5 5))) ⇒ ((1 (1 (1))) (1 (2 (3))) (5 (5 (5)))) (funcall (-applify '<) '(3 6)) ⇒ t
-- Function: -on (operator transformer) Return a function of two arguments that first applies TRANSFORMER to each of them and then applies OPERATOR on the results (in the same order).
In types: (b -> b -> c) -> (a -> b) -> a -> a -> c
(-sort (-on '< 'length) '((1 2 3) (1) (1 2))) ⇒ ((1) (1 2) (1 2 3)) (-min-by (-on '> 'length) '((1 2 3) (4) (1 2))) ⇒ (4) (-min-by (-on 'string-lessp 'number-to-string) '(2 100 22)) ⇒ 22
-- Function: -flip (func) Swap the order of arguments for binary function FUNC.
In types: (a -> b -> c) -> b -> a -> c
(funcall (-flip '<) 2 1) ⇒ t (funcall (-flip '-) 3 8) ⇒ 5 (-sort (-flip '<) '(4 3 6 1)) ⇒ (6 4 3 1)
-- Function: -const (c) Return a function that returns C ignoring any additional arguments.
In types: a -> b -> a
(funcall (-const 2) 1 3 "foo") ⇒ 2 (-map (-const 1) '("a" "b" "c" "d")) ⇒ (1 1 1 1) (-sum (-map (-const 1) '("a" "b" "c" "d"))) ⇒ 4
-- Macro: -cut (&rest params) Take n-ary function and n arguments and specialize some of them. Arguments denoted by <> will be left unspecialized.
See SRFI-26 for detailed description.
(funcall (-cut list 1 <> 3 <> 5) 2 4) ⇒ (1 2 3 4 5) (-map (-cut funcall <> 5) `(1+ 1- ,(lambda (x) (/ 1.0 x)))) ⇒ (6 4 0.2) (-map (-cut <> 1 2 3) '(list vector string)) ⇒ ((1 2 3) [1 2 3] "\1\2\3")
-- Function: -not (pred) Take a unary predicate PRED and return a unary predicate that returns t if PRED returns nil and nil if PRED returns non-nil.
(funcall (-not 'even?) 5) ⇒ t (-filter (-not (-partial '< 4)) '(1 2 3 4 5 6 7 8)) ⇒ (1 2 3 4)
-- Function: -orfn (&rest preds) Take list of unary predicates PREDS and return a unary predicate with argument x that returns non-nil if at least one of the PREDS returns non-nil on x.
In types: [a -> Bool] -> a -> Bool
(-filter (-orfn 'even? (-partial (-flip '<) 5)) '(1 2 3 4 5 6 7 8 9 10)) ⇒ (1 2 3 4 6 8 10) (funcall (-orfn 'stringp 'even?) "foo") ⇒ t
-- Function: -andfn (&rest preds) Take list of unary predicates PREDS and return a unary predicate with argument x that returns non-nil if all of the PREDS returns non-nil on x.
In types: [a -> Bool] -> a -> Bool
(funcall (-andfn (-cut < <> 10) 'even?) 6) ⇒ t (funcall (-andfn (-cut < <> 10) 'even?) 12) ⇒ nil (-filter (-andfn (-not 'even?) (-cut >= 5 <>)) '(1 2 3 4 5 6 7 8 9 10)) ⇒ (1 3 5)
-- Function: -iteratefn (fn n) Return a function FN composed N times with itself.
FN is a unary function. If you need to use a function of higher arity, use ‘-applify’ (*note -applify::) first to turn it into a unary function.
With n = 0, this acts as identity function.
In types: (a -> a) -> Int -> a -> a.
This function satisfies the following law:
(funcall (-iteratefn fn n) init) = (-last-item (-iterate fn init (1+ n))).
(funcall (-iteratefn (lambda (x) (* x x)) 3) 2) ⇒ 256 (funcall (-iteratefn '1+ 3) 1) ⇒ 4 (funcall (-iteratefn 'cdr 3) '(1 2 3 4 5)) ⇒ (4 5)
-- Function: -fixfn (fn &optional equal-test halt-test) Return a function that computes the (least) fixpoint of FN.
FN must be a unary function. The returned lambda takes a single argument, X, the initial value for the fixpoint iteration. The iteration halts when either of the following conditions is satisfied:
1. Iteration converges to the fixpoint, with equality being tested using EQUAL-TEST. If EQUAL-TEST is not specified, ‘equal’ is used. For functions over the floating point numbers, it may be necessary to provide an appropriate approximate comparison test.
2. HALT-TEST returns a non-nil value. HALT-TEST defaults to a simple counter that returns t after ‘-fixfn-max-iterations’, to guard against infinite iteration. Otherwise, HALT-TEST must be a function that accepts a single argument, the current value of X, and returns non-nil as long as iteration should continue. In this way, a more sophisticated convergence test may be supplied by the caller.
The return value of the lambda is either the fixpoint or, if iteration halted before converging, a cons with car ‘halted’ and cdr the final output from HALT-TEST.
In types: (a -> a) -> a -> a.
(funcall (-fixfn #'cos #'approx=) 0.7) ⇒ 0.7390851332151607 (funcall (-fixfn (lambda (x) (expt (+ x 10) 0.25))) 2.0) ⇒ 1.8555845286409378 (funcall (-fixfn #'sin #'approx=) 0.1) ⇒ (halted . t)
-- Function: -prodfn (&rest fns) Take a list of n functions and return a function that takes a list of length n, applying i-th function to i-th element of the input list. Returns a list of length n.
In types (for n=2): ((a -> b), (c -> d)) -> (a, c) -> (b, d)
This function satisfies the following laws:
(-compose (-prodfn f g ...) (-prodfn f’ g’ ...)) = (-prodfn (-compose f f’) (-compose g g’) ...) (-prodfn f g ...) = (-juxt (-compose f (-partial ’nth 0)) (-compose g (-partial ’nth 1)) ...) (-compose (-prodfn f g ...) (-juxt f’ g’ ...)) = (-juxt (-compose f f’) (-compose g g’) ...) (-compose (-partial ’nth n) (-prod f1 f2 ...)) = (-compose fn (-partial ’nth n))
(funcall (-prodfn '1+ '1- 'number-to-string) '(1 2 3)) ⇒ (2 1 "3") (-map (-prodfn '1+ '1-) '((1 2) (3 4) (5 6) (7 8))) ⇒ ((2 1) (4 3) (6 5) (8 7)) (apply '+ (funcall (-prodfn 'length 'string-to-number) '((1 2 3) "15"))) ⇒ 18
File: dash.info, Node: Development, Next: FDL, Prev: Functions, Up: Top
3 Development*************
The Dash repository is hosted on GitHub at<https://github.com/magnars/dash.el>.
* Menu:
* Contribute:: How to contribute.* Contributors:: List of contributors.
File: dash.info, Node: Contribute, Next: Contributors, Up: Development
3.1 Contribute==============
Yes, please do. Pure functions in the list manipulation realm only,please. There’s a suite of examples/tests in ‘dev/examples.el’, soremember to add tests for your additions, or they may get broken later.
Run the tests with ‘make check’. Regenerate the docs with ‘makedocs’. Contributors are encouraged to install these commands as a Gitpre-commit hook, so that the tests are always running and the docs arealways in sync:
$ cp dev/pre-commit.sh .git/hooks/pre-commit
Oh, and don’t edit ‘README.md’ or ‘dash.texi’ directly, as they areauto-generated. Instead, change their respective templates‘readme-template.md’ or ‘dash-template.texi’.
To ensure that Dash can be distributed with GNU ELPA or Emacs, werequire that all contributors assign copyright to the Free SoftwareFoundation. For more on this, *note (emacs)Copyright Assignment::.
File: dash.info, Node: Contributors, Prev: Contribute, Up: Development
3.2 Contributors================
• Matus Goljer (https://github.com/Fuco1) contributed lots of features and functions. • Takafumi Arakaki (https://github.com/tkf) contributed ‘-group-by’. • tali713 (https://github.com/tali713) is the author of ‘-applify’. • Víctor M. Valenzuela (https://github.com/vemv) contributed ‘-repeat’. • Nic Ferrier (https://github.com/nicferrier) contributed ‘-cons*’. • Wilfred Hughes (https://github.com/Wilfred) contributed ‘-slice’, ‘-first-item’, and ‘-last-item’. • Emanuel Evans (https://github.com/shosti) contributed ‘-if-let’, ‘-when-let’, and ‘-insert-at’. • Johan Andersson (https://github.com/rejeep) contributed ‘-sum’, ‘-product’, and ‘-same-items?’. • Christina Whyte (https://github.com/kurisuwhyte) contributed ‘-compose’. • Steve Lamb (https://github.com/steventlamb) contributed ‘-cycle’, ‘-pad’, ‘-annotate’, ‘-zip-fill’, and a variadic version of ‘-zip’. • Fredrik Bergroth (https://github.com/fbergroth) made the ‘-if-let’ family use ‘-let’ destructuring and improved the script for generating documentation. • Mark Oteiza (https://github.com/holomorph) contributed ‘-iota’ and the script to create an Info manual. • Vasilij Schneidermann (https://github.com/wasamasa) contributed ‘-some’. • William West (https://github.com/occidens) made ‘-fixfn’ more robust at handling floats. • Cam Saul (https://github.com/camsaul) contributed ‘-some->’, ‘-some->>’, and ‘-some-->’. • Basil L. Contovounesios (https://github.com/basil-conto) contributed ‘-common-prefix’, ‘-common-suffix’, and various other improvements. • Paul Pogonyshev (https://github.com/doublep) contributed ‘-each-r’ and ‘-each-r-while’.
Thanks!
New contributors are very welcome. *Note Contribute::.
File: dash.info, Node: FDL, Next: GPL, Prev: Development, Up: Top
Appendix A GNU Free Documentation License*****************************************
Version 1.3, 3 November 2008
Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. <https://fsf.org/>
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
0. PREAMBLE
The purpose of this License is to make a manual, textbook, or other functional and useful document “free” in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.
This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.
We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.
1. APPLICABILITY AND DEFINITIONS
This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.
A “Modified Version” of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.
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The “Invariant Sections” are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.
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2. VERBATIM COPYING
You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.
You may also lend copies, under the same conditions stated above, and you may publicly display copies.
3. COPYING IN QUANTITY
If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.
If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.
If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.
It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.
4. MODIFICATIONS
You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:
A. Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). You may use the same title as a previous version if the original publisher of that version gives permission.
B. List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has fewer than five), unless they release you from this requirement.
C. State on the Title page the name of the publisher of the Modified Version, as the publisher.
D. Preserve all the copyright notices of the Document.
E. Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.
F. Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.
G. Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document’s license notice.
H. Include an unaltered copy of this License.
I. Preserve the section Entitled “History”, Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled “History” in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.
J. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the “History” section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.
K. For any section Entitled “Acknowledgements” or “Dedications”, Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.
L. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.
M. Delete any section Entitled “Endorsements”. Such a section may not be included in the Modified Version.
N. Do not retitle any existing section to be Entitled “Endorsements” or to conflict in title with any Invariant Section.
O. Preserve any Warranty Disclaimers.
If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.
You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.
You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.
The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.
5. COMBINING DOCUMENTS
You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.
The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.
In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”
6. COLLECTIONS OF DOCUMENTS
You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.
You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.
7. AGGREGATION WITH INDEPENDENT WORKS
A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.
8. TRANSLATION
Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.
If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.
9. TERMINATION
You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.
10. FUTURE REVISIONS OF THIS LICENSE
The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See <https://www.gnu.org/licenses/>.
Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.
11. RELICENSING
“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.
“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.
“Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.
An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.
The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.
ADDENDUM: How to use this License for your documents====================================================
To use this License in a document you have written, include a copy ofthe License in the document and put the following copyright and licensenotices just after the title page:
Copyright (C) YEAR YOUR NAME. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''.
If you have Invariant Sections, Front-Cover Texts and Back-CoverTexts, replace the “with...Texts.” line with this:
with the Invariant Sections being LIST THEIR TITLES, with the Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
If you have Invariant Sections without Cover Texts, or some othercombination of the three, merge those two alternatives to suit thesituation.
If your document contains nontrivial examples of program code, werecommend releasing these examples in parallel under your choice of freesoftware license, such as the GNU General Public License, to permittheir use in free software.
File: dash.info, Node: GPL, Next: Index, Prev: FDL, Up: Top
Appendix B GNU General Public License*************************************
Version 3, 29 June 2007
Copyright © 2007 Free Software Foundation, Inc. <https://fsf.org/>
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
Preamble========
The GNU General Public License is a free, copyleft license for softwareand other kinds of works.
The licenses for most software and other practical works are designedto take away your freedom to share and change the works. By contrast,the GNU General Public License is intended to guarantee your freedom toshare and change all versions of a program—to make sure it remains freesoftware for all its users. We, the Free Software Foundation, use theGNU General Public License for most of our software; it applies also toany other work released this way by its authors. You can apply it toyour programs, too.
When we speak of free software, we are referring to freedom, notprice. Our General Public Licenses are designed to make sure that youhave the freedom to distribute copies of free software (and charge forthem if you wish), that you receive source code or can get it if youwant it, that you can change the software or use pieces of it in newfree programs, and that you know you can do these things.
To protect your rights, we need to prevent others from denying youthese rights or asking you to surrender the rights. Therefore, you havecertain responsibilities if you distribute copies of the software, or ifyou modify it: responsibilities to respect the freedom of others.
For example, if you distribute copies of such a program, whethergratis or for a fee, you must pass on to the recipients the samefreedoms that you received. You must make sure that they, too, receiveor can get the source code. And you must show them these terms so theyknow their rights.
Developers that use the GNU GPL protect your rights with two steps:(1) assert copyright on the software, and (2) offer you this Licensegiving you legal permission to copy, distribute and/or modify it.
For the developers’ and authors’ protection, the GPL clearly explainsthat there is no warranty for this free software. For both users’ andauthors’ sake, the GPL requires that modified versions be marked aschanged, so that their problems will not be attributed erroneously toauthors of previous versions.
Some devices are designed to deny users access to install or runmodified versions of the software inside them, although the manufacturercan do so. This is fundamentally incompatible with the aim ofprotecting users’ freedom to change the software. The systematicpattern of such abuse occurs in the area of products for individuals touse, which is precisely where it is most unacceptable. Therefore, wehave designed this version of the GPL to prohibit the practice for thoseproducts. If such problems arise substantially in other domains, westand ready to extend this provision to those domains in future versionsof the GPL, as needed to protect the freedom of users.
Finally, every program is threatened constantly by software patents.States should not allow patents to restrict development and use ofsoftware on general-purpose computers, but in those that do, we wish toavoid the special danger that patents applied to a free program couldmake it effectively proprietary. To prevent this, the GPL assures thatpatents cannot be used to render the program non-free.
The precise terms and conditions for copying, distribution andmodification follow.
TERMS AND CONDITIONS====================
0. Definitions.
“This License” refers to version 3 of the GNU General Public License.
“Copyright” also means copyright-like laws that apply to other kinds of works, such as semiconductor masks.
“The Program” refers to any copyrightable work licensed under this License. Each licensee is addressed as “you”. “Licensees” and “recipients” may be individuals or organizations.
To “modify” a work means to copy from or adapt all or part of the work in a fashion requiring copyright permission, other than the making of an exact copy. The resulting work is called a “modified version” of the earlier work or a work “based on” the earlier work.
A “covered work” means either the unmodified Program or a work based on the Program.
To “propagate” a work means to do anything with it that, without permission, would make you directly or secondarily liable for infringement under applicable copyright law, except executing it on a computer or modifying a private copy. Propagation includes copying, distribution (with or without modification), making available to the public, and in some countries other activities as well.
To “convey” a work means any kind of propagation that enables other parties to make or receive copies. Mere interaction with a user through a computer network, with no transfer of a copy, is not conveying.
An interactive user interface displays “Appropriate Legal Notices” to the extent that it includes a convenient and prominently visible feature that (1) displays an appropriate copyright notice, and (2) tells the user that there is no warranty for the work (except to the extent that warranties are provided), that licensees may convey the work under this License, and how to view a copy of this License. If the interface presents a list of user commands or options, such as a menu, a prominent item in the list meets this criterion.
1. Source Code.
The “source code” for a work means the preferred form of the work for making modifications to it. “Object code” means any non-source form of a work.
A “Standard Interface” means an interface that either is an official standard defined by a recognized standards body, or, in the case of interfaces specified for a particular programming language, one that is widely used among developers working in that language.
The “System Libraries” of an executable work include anything, other than the work as a whole, that (a) is included in the normal form of packaging a Major Component, but which is not part of that Major Component, and (b) serves only to enable use of the work with that Major Component, or to implement a Standard Interface for which an implementation is available to the public in source code form. A “Major Component”, in this context, means a major essential component (kernel, window system, and so on) of the specific operating system (if any) on which the executable work runs, or a compiler used to produce the work, or an object code interpreter used to run it.
The “Corresponding Source” for a work in object code form means all the source code needed to generate, install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities. However, it does not include the work’s System Libraries, or general-purpose tools or generally available free programs which are used unmodified in performing those activities but which are not part of the work. For example, Corresponding Source includes interface definition files associated with source files for the work, and the source code for shared libraries and dynamically linked subprograms that the work is specifically designed to require, such as by intimate data communication or control flow between those subprograms and other parts of the work.
The Corresponding Source need not include anything that users can regenerate automatically from other parts of the Corresponding Source.
The Corresponding Source for a work in source code form is that same work.
2. Basic Permissions.
All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met. This License explicitly affirms your unlimited permission to run the unmodified Program. The output from running a covered work is covered by this License only if the output, given its content, constitutes a covered work. This License acknowledges your rights of fair use or other equivalent, as provided by copyright law.
You may make, run and propagate covered works that you do not convey, without conditions so long as your license otherwise remains in force. You may convey covered works to others for the sole purpose of having them make modifications exclusively for you, or provide you with facilities for running those works, provided that you comply with the terms of this License in conveying all material for which you do not control copyright. Those thus making or running the covered works for you must do so exclusively on your behalf, under your direction and control, on terms that prohibit them from making any copies of your copyrighted material outside their relationship with you.
Conveying under any other circumstances is permitted solely under the conditions stated below. Sublicensing is not allowed; section 10 makes it unnecessary.
3. Protecting Users’ Legal Rights From Anti-Circumvention Law.
No covered work shall be deemed part of an effective technological measure under any applicable law fulfilling obligations under article 11 of the WIPO copyright treaty adopted on 20 December 1996, or similar laws prohibiting or restricting circumvention of such measures.
When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the extent such circumvention is effected by exercising rights under this License with respect to the covered work, and you disclaim any intention to limit operation or modification of the work as a means of enforcing, against the work’s users, your or third parties’ legal rights to forbid circumvention of technological measures.
4. Conveying Verbatim Copies.
You may convey verbatim copies of the Program’s source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all notices stating that this License and any non-permissive terms added in accord with section 7 apply to the code; keep intact all notices of the absence of any warranty; and give all recipients a copy of this License along with the Program.
You may charge any price or no price for each copy that you convey, and you may offer support or warranty protection for a fee.
5. Conveying Modified Source Versions.
You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source code under the terms of section 4, provided that you also meet all of these conditions:
a. The work must carry prominent notices stating that you modified it, and giving a relevant date.
b. The work must carry prominent notices stating that it is released under this License and any conditions added under section 7. This requirement modifies the requirement in section 4 to “keep intact all notices”.
c. You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it.
d. If the work has interactive user interfaces, each must display Appropriate Legal Notices; however, if the Program has interactive interfaces that do not display Appropriate Legal Notices, your work need not make them do so.
A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an “aggregate” if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation’s users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate.
6. Conveying Non-Source Forms.
You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways:
a. Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by the Corresponding Source fixed on a durable physical medium customarily used for software interchange.
b. Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give anyone who possesses the object code either (1) a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange, for a price no more than your reasonable cost of physically performing this conveying of source, or (2) access to copy the Corresponding Source from a network server at no charge.
c. Convey individual copies of the object code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only occasionally and noncommercially, and only if you received the object code with such an offer, in accord with subsection 6b.
d. Convey the object code by offering access from a designated place (gratis or for a charge), and offer equivalent access to the Corresponding Source in the same way through the same place at no further charge. You need not require recipients to copy the Corresponding Source along with the object code. If the place to copy the object code is a network server, the Corresponding Source may be on a different server (operated by you or a third party) that supports equivalent copying facilities, provided you maintain clear directions next to the object code saying where to find the Corresponding Source. Regardless of what server hosts the Corresponding Source, you remain obligated to ensure that it is available for as long as needed to satisfy these requirements.
e. Convey the object code using peer-to-peer transmission, provided you inform other peers where the object code and Corresponding Source of the work are being offered to the general public at no charge under subsection 6d.
A separable portion of the object code, whose source code is excluded from the Corresponding Source as a System Library, need not be included in conveying the object code work.
A “User Product” is either (1) a “consumer product”, which means any tangible personal property which is normally used for personal, family, or household purposes, or (2) anything designed or sold for incorporation into a dwelling. In determining whether a product is a consumer product, doubtful cases shall be resolved in favor of coverage. For a particular product received by a particular user, “normally used” refers to a typical or common use of that class of product, regardless of the status of the particular user or of the way in which the particular user actually uses, or expects or is expected to use, the product. A product is a consumer product regardless of whether the product has substantial commercial, industrial or non-consumer uses, unless such uses represent the only significant mode of use of the product.
“Installation Information” for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.
If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM).
The requirement to provide Installation Information does not include a requirement to continue to provide support service, warranty, or updates for a work that has been modified or installed by the recipient, or for the User Product in which it has been modified or installed. Access to a network may be denied when the modification itself materially and adversely affects the operation of the network or violates the rules and protocols for communication across the network.
Corresponding Source conveyed, and Installation Information provided, in accord with this section must be in a format that is publicly documented (and with an implementation available to the public in source code form), and must require no special password or key for unpacking, reading or copying.
7. Additional Terms.
“Additional permissions” are terms that supplement the terms of this License by making exceptions from one or more of its conditions. Additional permissions that are applicable to the entire Program shall be treated as though they were included in this License, to the extent that they are valid under applicable law. If additional permissions apply only to part of the Program, that part may be used separately under those permissions, but the entire Program remains governed by this License without regard to the additional permissions.
When you convey a copy of a covered work, you may at your option remove any additional permissions from that copy, or from any part of it. (Additional permissions may be written to require their own removal in certain cases when you modify the work.) You may place additional permissions on material, added by you to a covered work, for which you have or can give appropriate copyright permission.
Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by the copyright holders of that material) supplement the terms of this License with terms:
a. Disclaiming warranty or limiting liability differently from the terms of sections 15 and 16 of this License; or
b. Requiring preservation of specified reasonable legal notices or author attributions in that material or in the Appropriate Legal Notices displayed by works containing it; or
c. Prohibiting misrepresentation of the origin of that material, or requiring that modified versions of such material be marked in reasonable ways as different from the original version; or
d. Limiting the use for publicity purposes of names of licensors or authors of the material; or
e. Declining to grant rights under trademark law for use of some trade names, trademarks, or service marks; or
f. Requiring indemnification of licensors and authors of that material by anyone who conveys the material (or modified versions of it) with contractual assumptions of liability to the recipient, for any liability that these contractual assumptions directly impose on those licensors and authors.
All other non-permissive additional terms are considered “further restrictions” within the meaning of section 10. If the Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with a term that is a further restriction, you may remove that term. If a license document contains a further restriction but permits relicensing or conveying under this License, you may add to a covered work material governed by the terms of that license document, provided that the further restriction does not survive such relicensing or conveying.
If you add terms to a covered work in accord with this section, you must place, in the relevant source files, a statement of the additional terms that apply to those files, or a notice indicating where to find the applicable terms.
Additional terms, permissive or non-permissive, may be stated in the form of a separately written license, or stated as exceptions; the above requirements apply either way.
8. Termination.
You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to propagate or modify it is void, and will automatically terminate your rights under this License (including any patent licenses granted under the third paragraph of section 11).
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, you do not qualify to receive new licenses for the same material under section 10.
9. Acceptance Not Required for Having Copies.
You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so.
10. Automatic Licensing of Downstream Recipients.
Each time you convey a covered work, the recipient automatically receives a license from the original licensors, to run, modify and propagate that work, subject to this License. You are not responsible for enforcing compliance by third parties with this License.
An “entity transaction” is a transaction transferring control of an organization, or substantially all assets of one, or subdividing an organization, or merging organizations. If propagation of a covered work results from an entity transaction, each party to that transaction who receives a copy of the work also receives whatever licenses to the work the party’s predecessor in interest had or could give under the previous paragraph, plus a right to possession of the Corresponding Source of the work from the predecessor in interest, if the predecessor has it or can get it with reasonable efforts.
You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or importing the Program or any portion of it.
11. Patents.
A “contributor” is a copyright holder who authorizes use under this License of the Program or a work on which the Program is based. The work thus licensed is called the contributor’s “contributor version”.
A contributor’s “essential patent claims” are all patent claims owned or controlled by the contributor, whether already acquired or hereafter acquired, that would be infringed by some manner, permitted by this License, of making, using, or selling its contributor version, but do not include claims that would be infringed only as a consequence of further modification of the contributor version. For purposes of this definition, “control” includes the right to grant patent sublicenses in a manner consistent with the requirements of this License.
Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor’s essential patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its contributor version.
In the following three paragraphs, a “patent license” is any express agreement or commitment, however denominated, not to enforce a patent (such as an express permission to practice a patent or covenant not to sue for patent infringement). To “grant” such a patent license to a party means to make such an agreement or commitment not to enforce a patent against the party.
If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of the work is not available for anyone to copy, free of charge and under the terms of this License, through a publicly available network server or other readily accessible means, then you must either (1) cause the Corresponding Source to be so available, or (2) arrange to deprive yourself of the benefit of the patent license for this particular work, or (3) arrange, in a manner consistent with the requirements of this License, to extend the patent license to downstream recipients. “Knowingly relying” means you have actual knowledge that, but for the patent license, your conveying the covered work in a country, or your recipient’s use of the covered work in a country, would infringe one or more identifiable patents in that country that you have reason to believe are valid.
If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring conveyance of, a covered work, and grant a patent license to some of the parties receiving the covered work authorizing them to use, propagate, modify or convey a specific copy of the covered work, then the patent license you grant is automatically extended to all recipients of the covered work and works based on it.
A patent license is “discriminatory” if it does not include within the scope of its coverage, prohibits the exercise of, or is conditioned on the non-exercise of one or more of the rights that are specifically granted under this License. You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software, under which you make payment to the third party based on the extent of your activity of conveying the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a discriminatory patent license (a) in connection with copies of the covered work conveyed by you (or copies made from those copies), or (b) primarily for and in connection with specific products or compilations that contain the covered work, unless you entered into that arrangement, or that patent license was granted, prior to 28 March 2007.
Nothing in this License shall be construed as excluding or limiting any implied license or other defenses to infringement that may otherwise be available to you under applicable patent law.
12. No Surrender of Others’ Freedom.
If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program.
13. Use with the GNU Affero General Public License.
Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply to the combination as such.
14. Revised Versions of this License.
The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.
Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of the GNU General Public License “or any later version” applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of the GNU General Public License, you may choose any version ever published by the Free Software Foundation.
If the Program specifies that a proxy can decide which future versions of the GNU General Public License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Program.
Later license versions may give you additional or different permissions. However, no additional obligations are imposed on any author or copyright holder as a result of your choosing to follow a later version.
15. Disclaimer of Warranty.
THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
16. Limitation of Liability.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
17. Interpretation of Sections 15 and 16.
If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee.
END OF TERMS AND CONDITIONS===========================
How to Apply These Terms to Your New Programs=============================================
If you develop a new program, and you want it to be of the greatestpossible use to the public, the best way to achieve this is to make itfree software which everyone can redistribute and change under theseterms.
To do so, attach the following notices to the program. It is safestto attach them to the start of each source file to most effectivelystate the exclusion of warranty; and each file should have at least the“copyright” line and a pointer to where the full notice is found.
ONE LINE TO GIVE THE PROGRAM'S NAME AND A BRIEF IDEA OF WHAT IT DOES. Copyright (C) YEAR NAME OF AUTHOR
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
Also add information on how to contact you by electronic and papermail.
If the program does terminal interaction, make it output a shortnotice like this when it starts in an interactive mode:
PROGRAM Copyright (C) YEAR NAME OF AUTHOR This program comes with ABSOLUTELY NO WARRANTY; for details type ‘show w’. This is free software, and you are welcome to redistribute it under certain conditions; type ‘show c’ for details.
The hypothetical commands ‘show w’ and ‘show c’ should show theappropriate parts of the General Public License. Of course, yourprogram’s commands might be different; for a GUI interface, you woulduse an “about box”.
You should also get your employer (if you work as a programmer) orschool, if any, to sign a “copyright disclaimer” for the program, ifnecessary. For more information on this, and how to apply and followthe GNU GPL, see <https://www.gnu.org/licenses/>.
The GNU General Public License does not permit incorporating yourprogram into proprietary programs. If your program is a subroutinelibrary, you may consider it more useful to permit linking proprietaryapplications with the library. If this is what you want to do, use theGNU Lesser General Public License instead of this License. But first,please read <https://www.gnu.org/licenses/why-not-lgpl.html>.
File: dash.info, Node: Index, Prev: GPL, Up: Top
Index*****
[index ]* Menu:
* !cdr: Destructive operations. (line 16)* !cons: Destructive operations. (line 8)* -->: Threading macros. (line 35)* ->: Threading macros. (line 9)* ->>: Threading macros. (line 22)* -all?: Predicates. (line 20)* -andfn: Function combinators. (line 137)* -annotate: Maps. (line 84)* -any?: Predicates. (line 8)* -applify: Function combinators. (line 54)* -as->: Threading macros. (line 49)* -butlast: Other list operations. (line 350)* -clone: Tree operations. (line 122)* -common-prefix: Reductions. (line 242)* -common-suffix: Reductions. (line 252)* -compose: Function combinators. (line 41)* -concat: List to list. (line 23)* -cons*: Other list operations. (line 30)* -cons-pair?: Predicates. (line 126)* -const: Function combinators. (line 91)* -contains?: Predicates. (line 59)* -copy: Maps. (line 139)* -count: Reductions. (line 172)* -cut: Function combinators. (line 103)* -cycle: Other list operations. (line 180)* -difference: Set operations. (line 20)* -distinct: Set operations. (line 62)* -dotimes: Side effects. (line 80)* -doto: Threading macros. (line 99)* -drop: Sublist selection. (line 147)* -drop-last: Sublist selection. (line 161)* -drop-while: Sublist selection. (line 192)* -each: Side effects. (line 8)* -each-indexed: Side effects. (line 38)* -each-r: Side effects. (line 52)* -each-r-while: Side effects. (line 65)* -each-while: Side effects. (line 24)* -elem-index: Indexing. (line 9)* -elem-indices: Indexing. (line 21)* -fifth-item: Other list operations. (line 330)* -filter: Sublist selection. (line 8)* -find-index: Indexing. (line 32)* -find-indices: Indexing. (line 60)* -find-last-index: Indexing. (line 46)* -first: Other list operations. (line 246)* -first-item: Other list operations. (line 287)* -fix: Other list operations. (line 390)* -fixfn: Function combinators. (line 174)* -flatten: List to list. (line 34)* -flatten-n: List to list. (line 56)* -flip: Function combinators. (line 79)* -fourth-item: Other list operations. (line 320)* -grade-down: Indexing. (line 81)* -grade-up: Indexing. (line 71)* -group-by: Partitioning. (line 193)* -if-let: Binding. (line 34)* -if-let*: Binding. (line 45)* -inits: Reductions. (line 222)* -insert-at: List to list. (line 110)* -interleave: Other list operations. (line 67)* -interpose: Other list operations. (line 57)* -intersection: Set operations. (line 32)* -iota: Other list operations. (line 78)* -is-infix?: Predicates. (line 112)* -is-prefix?: Predicates. (line 88)* -is-suffix?: Predicates. (line 100)* -iterate: Unfolding. (line 9)* -iteratefn: Function combinators. (line 151)* -juxt: Function combinators. (line 30)* -keep: List to list. (line 8)* -lambda: Binding. (line 247)* -last: Other list operations. (line 277)* -last-item: Other list operations. (line 340)* -let: Binding. (line 61)* -let*: Binding. (line 227)* -list: Other list operations. (line 373)* -map: Maps. (line 10)* -map-first: Maps. (line 38)* -map-indexed: Maps. (line 66)* -map-last: Maps. (line 52)* -map-when: Maps. (line 22)* -mapcat: Maps. (line 128)* -max: Reductions. (line 286)* -max-by: Reductions. (line 296)* -min: Reductions. (line 262)* -min-by: Reductions. (line 272)* -non-nil: Sublist selection. (line 94)* -none?: Predicates. (line 32)* -not: Function combinators. (line 116)* -on: Function combinators. (line 65)* -only-some?: Predicates. (line 44)* -orfn: Function combinators. (line 125)* -pad: Other list operations. (line 191)* -partial: Function combinators. (line 8)* -partition: Partitioning. (line 80)* -partition-after-item: Partitioning. (line 183)* -partition-after-pred: Partitioning. (line 151)* -partition-all: Partitioning. (line 92)* -partition-all-in-steps: Partitioning. (line 115)* -partition-before-item: Partitioning. (line 173)* -partition-before-pred: Partitioning. (line 162)* -partition-by: Partitioning. (line 127)* -partition-by-header: Partitioning. (line 138)* -partition-in-steps: Partitioning. (line 103)* -permutations: Set operations. (line 52)* -powerset: Set operations. (line 44)* -prodfn: Function combinators. (line 208)* -product: Reductions. (line 201)* -reduce: Reductions. (line 53)* -reduce-from: Reductions. (line 8)* -reduce-r: Reductions. (line 72)* -reduce-r-from: Reductions. (line 26)* -reductions: Reductions. (line 136)* -reductions-from: Reductions. (line 100)* -reductions-r: Reductions. (line 154)* -reductions-r-from: Reductions. (line 118)* -remove: Sublist selection. (line 26)* -remove-at: List to list. (line 146)* -remove-at-indices: List to list. (line 159)* -remove-first: Sublist selection. (line 43)* -remove-item: Sublist selection. (line 83)* -remove-last: Sublist selection. (line 64)* -repeat: Other list operations. (line 19)* -replace: List to list. (line 68)* -replace-at: List to list. (line 121)* -replace-first: List to list. (line 82)* -replace-last: List to list. (line 96)* -rotate: Other list operations. (line 8)* -rpartial: Function combinators. (line 19)* -running-product: Reductions. (line 211)* -running-sum: Reductions. (line 190)* -same-items?: Predicates. (line 74)* -second-item: Other list operations. (line 300)* -select-by-indices: Sublist selection. (line 208)* -select-column: Sublist selection. (line 238)* -select-columns: Sublist selection. (line 219)* -separate: Partitioning. (line 69)* -setq: Binding. (line 270)* -slice: Sublist selection. (line 104)* -snoc: Other list operations. (line 43)* -some: Other list operations. (line 262)* -some-->: Threading macros. (line 86)* -some->: Threading macros. (line 62)* -some->>: Threading macros. (line 74)* -sort: Other list operations. (line 360)* -splice: Maps. (line 95)* -splice-list: Maps. (line 115)* -split-at: Partitioning. (line 8)* -split-on: Partitioning. (line 34)* -split-when: Partitioning. (line 52)* -split-with: Partitioning. (line 23)* -sum: Reductions. (line 180)* -table: Other list operations. (line 202)* -table-flat: Other list operations. (line 221)* -tails: Reductions. (line 232)* -take: Sublist selection. (line 120)* -take-last: Sublist selection. (line 133)* -take-while: Sublist selection. (line 175)* -third-item: Other list operations. (line 310)* -tree-map: Tree operations. (line 28)* -tree-map-nodes: Tree operations. (line 39)* -tree-mapreduce: Tree operations. (line 84)* -tree-mapreduce-from: Tree operations. (line 103)* -tree-reduce: Tree operations. (line 52)* -tree-reduce-from: Tree operations. (line 69)* -tree-seq: Tree operations. (line 8)* -unfold: Unfolding. (line 25)* -union: Set operations. (line 8)* -unzip: Other list operations. (line 158)* -update-at: List to list. (line 133)* -when-let: Binding. (line 9)* -when-let*: Binding. (line 21)* -zip: Other list operations. (line 107)* -zip-fill: Other list operations. (line 150)* -zip-lists: Other list operations. (line 131)* -zip-with: Other list operations. (line 91)* dash-fontify-mode: Fontification of special variables. (line 6)* dash-register-info-lookup: Info symbol lookup. (line 6)* global-dash-fontify-mode: Fontification of special variables. (line 12)
Tag Table:Node: Top742Node: Installation2397Node: Using in a package3112Node: Fontification of special variables3457Node: Info symbol lookup4247Node: Functions4830Node: Maps6314Ref: -map6611Ref: -map-when6984Ref: -map-first7559Ref: -map-last8034Ref: -map-indexed8504Ref: -annotate9190Ref: -splice9677Ref: -splice-list10455Ref: -mapcat10914Ref: -copy11287Node: Sublist selection11475Ref: -filter11668Ref: -remove12215Ref: -remove-first12753Ref: -remove-last13595Ref: -remove-item14320Ref: -non-nil14720Ref: -slice14996Ref: -take15525Ref: -take-last15932Ref: -drop16363Ref: -drop-last16804Ref: -take-while17230Ref: -drop-while17845Ref: -select-by-indices18461Ref: -select-columns18972Ref: -select-column19675Node: List to list20138Ref: -keep20330Ref: -concat20894Ref: -flatten21188Ref: -flatten-n21944Ref: -replace22328Ref: -replace-first22789Ref: -replace-last23284Ref: -insert-at23772Ref: -replace-at24097Ref: -update-at24484Ref: -remove-at24972Ref: -remove-at-indices25457Node: Reductions26036Ref: -reduce-from26232Ref: -reduce-r-from26956Ref: -reduce28219Ref: -reduce-r28970Ref: -reductions-from30248Ref: -reductions-r-from31054Ref: -reductions31884Ref: -reductions-r32595Ref: -count33340Ref: -sum33564Ref: -running-sum33752Ref: -product34073Ref: -running-product34281Ref: -inits34622Ref: -tails34867Ref: -common-prefix35111Ref: -common-suffix35405Ref: -min35699Ref: -min-by35925Ref: -max36446Ref: -max-by36671Node: Unfolding37197Ref: -iterate37438Ref: -unfold37885Node: Predicates38690Ref: -any?38867Ref: -all?39187Ref: -none?39517Ref: -only-some?39819Ref: -contains?40304Ref: -same-items?40693Ref: -is-prefix?41078Ref: -is-suffix?41404Ref: -is-infix?41730Ref: -cons-pair?42084Node: Partitioning42409Ref: -split-at42597Ref: -split-with43261Ref: -split-on43661Ref: -split-when44334Ref: -separate44971Ref: -partition45410Ref: -partition-all45859Ref: -partition-in-steps46284Ref: -partition-all-in-steps46778Ref: -partition-by47260Ref: -partition-by-header47638Ref: -partition-after-pred48239Ref: -partition-before-pred48617Ref: -partition-before-item49002Ref: -partition-after-item49309Ref: -group-by49611Node: Indexing50044Ref: -elem-index50246Ref: -elem-indices50641Ref: -find-index51021Ref: -find-last-index51510Ref: -find-indices52014Ref: -grade-up52419Ref: -grade-down52826Node: Set operations53240Ref: -union53423Ref: -difference53861Ref: -intersection54273Ref: -powerset54705Ref: -permutations54915Ref: -distinct55211Node: Other list operations55585Ref: -rotate55810Ref: -repeat56177Ref: -cons*56456Ref: -snoc56872Ref: -interpose57282Ref: -interleave57576Ref: -iota57942Ref: -zip-with58425Ref: -zip59139Ref: -zip-lists59968Ref: -zip-fill60666Ref: -unzip60988Ref: -cycle61730Ref: -pad62129Ref: -table62448Ref: -table-flat63234Ref: -first64239Ref: -some64725Ref: -last65209Ref: -first-item65543Ref: -second-item65942Ref: -third-item66206Ref: -fourth-item66468Ref: -fifth-item66734Ref: -last-item66996Ref: -butlast67287Ref: -sort67532Ref: -list68018Ref: -fix68587Node: Tree operations69076Ref: -tree-seq69272Ref: -tree-map70127Ref: -tree-map-nodes70567Ref: -tree-reduce71414Ref: -tree-reduce-from72296Ref: -tree-mapreduce72896Ref: -tree-mapreduce-from73755Ref: -clone75040Node: Threading macros75367Ref: ->75592Ref: ->>76080Ref: -->76583Ref: -as->77139Ref: -some->77593Ref: -some->>77966Ref: -some-->78401Ref: -doto78950Node: Binding79503Ref: -when-let79710Ref: -when-let*80165Ref: -if-let80688Ref: -if-let*81048Ref: -let81665Ref: -let*87737Ref: -lambda88674Ref: -setq89480Node: Side effects90281Ref: -each90475Ref: -each-while90996Ref: -each-indexed91598Ref: -each-r92184Ref: -each-r-while92620Ref: -dotimes93246Node: Destructive operations93799Ref: !cons94017Ref: !cdr94221Node: Function combinators94414Ref: -partial94618Ref: -rpartial95012Ref: -juxt95415Ref: -compose95845Ref: -applify96398Ref: -on96827Ref: -flip97351Ref: -const97662Ref: -cut98000Ref: -not98480Ref: -orfn98789Ref: -andfn99222Ref: -iteratefn99716Ref: -fixfn100418Ref: -prodfn101974Node: Development103032Node: Contribute103321Node: Contributors104333Node: FDL106426Node: GPL131746Node: Index169495 End Tag Table
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