From e5503751c4a3279055c4714a91c39affabb8c461 Mon Sep 17 00:00:00 2001 From: William Carroll Date: Fri, 5 Aug 2022 12:34:15 -0700 Subject: feat(wpcarro/emacs): Add fns to list.el new functions: - duplicate - last - delete - wrap also: - drop support for `list-head` (in favor of `list-first`) - add optional arg to first Change-Id: If3c48d4749a3bc5a853995996fa02a65a4076a10 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6041 Reviewed-by: wpcarro Autosubmit: wpcarro Tested-by: BuildkiteCI --- users/wpcarro/emacs/.emacs.d/wpc/irc.el | 2 +- users/wpcarro/emacs/.emacs.d/wpc/stack.el | 2 +- users/wpcarro/emacs/pkgs/list/list.el | 40 ++++++++++++++++++++++++------- users/wpcarro/emacs/pkgs/list/tests.el | 36 ++++++++++++++++++++++++++++ 4 files changed, 70 insertions(+), 10 deletions(-) diff --git a/users/wpcarro/emacs/.emacs.d/wpc/irc.el b/users/wpcarro/emacs/.emacs.d/wpc/irc.el index 70d26f7f08..4ae50b4b1b 100644 --- a/users/wpcarro/emacs/.emacs.d/wpc/irc.el +++ b/users/wpcarro/emacs/.emacs.d/wpc/irc.el @@ -106,7 +106,7 @@ (let ((buffers (erc-buffer-list))) (if (list-empty? buffers) (error "[irc.el] No ERC buffers available") - (switch-to-buffer (list-head (erc-buffer-list)))))) + (switch-to-buffer (list-first (erc-buffer-list)))))) (defun irc-connect-to-freenode () "Connect to Freenode IRC." diff --git a/users/wpcarro/emacs/.emacs.d/wpc/stack.el b/users/wpcarro/emacs/.emacs.d/wpc/stack.el index 3d1e3e4a16..e81cec6a45 100644 --- a/users/wpcarro/emacs/.emacs.d/wpc/stack.el +++ b/users/wpcarro/emacs/.emacs.d/wpc/stack.el @@ -46,7 +46,7 @@ "Look at the top element of `XS' without popping it off." (->> xs stack-xs - list-head)) + list-first)) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Update diff --git a/users/wpcarro/emacs/pkgs/list/list.el b/users/wpcarro/emacs/pkgs/list/list.el index 2aa226609d..a395eba267 100644 --- a/users/wpcarro/emacs/pkgs/list/list.el +++ b/users/wpcarro/emacs/pkgs/list/list.el @@ -68,6 +68,10 @@ "Joins `LISTS' into on list." (apply #'-concat lists)) +(defun list-duplicate (n x) + "Duplicates the given element, X, N times in a list." + (list-map (lambda (_) x) (number-sequence 1 n))) + (defun list-join (joint xs) "Join a list of strings, XS, with JOINT." (if (list-empty? xs) @@ -85,14 +89,17 @@ "Return the value in `XS' at `I', or nil." (nth i xs)) -(defun list-head (xs) - "Return the head of `XS'." - (car xs)) - -;; TODO: Learn how to write proper function aliases. -(defun list-first (xs) +(defun list-first (xs &optional default) "Alias for `list-head' for `XS'." - (list-head xs)) + (if (list-empty? xs) + default + (car xs))) + +(defun list-last (xs &optional default) + "Returns the last element in XS or DEFAULT if empty." + (if (list-empty? xs) + default + (nth (- (length xs) 1) xs))) (defun list-tail (xs) "Return the tail of `XS'." @@ -106,6 +113,17 @@ "Add `X' to the head of `XS'." (cons x xs)) +(defun list-delete (x xs) + "Deletes the given element, X, from XS. +Returns a new list without X. If X occurs more than once, only the first + occurrence is removed." + (let ((deleted? nil)) + (list-reject (lambda (y) + (if deleted? nil + (when (equal x y) + (setq deleted? t) t))) + xs))) + (defun list-filter (p xs) "Return a subset of XS where predicate P returned t." (list--assert-instance xs) @@ -202,13 +220,19 @@ Be leery of using this with things like alists. Many data structures in Elisp (defun list-contains? (x xs) "Return t if X is in XS using `equal'." (list--assert-instance xs) - (maybe-some? (seq-contains xs x))) + (maybe-some? (seq-contains-p xs x))) (defun list-xs-distinct-by? (f xs) "Return t if all elements in XS are distinct after applying F to each." (= (length xs) (set-count (set-from-list (list-map f xs))))) +(defun list-wrap (xs) + "Wraps XS in a list if it is not a list already." + (if (list-instance? xs) + xs + (list xs))) + ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Helpers ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; diff --git a/users/wpcarro/emacs/pkgs/list/tests.el b/users/wpcarro/emacs/pkgs/list/tests.el index e2fb5788d6..4ee03c6b97 100644 --- a/users/wpcarro/emacs/pkgs/list/tests.el +++ b/users/wpcarro/emacs/pkgs/list/tests.el @@ -65,3 +65,39 @@ (should (null (list-any? (lambda (x) (= 2 x)) nil))) (should (equal t (list-any? (lambda (x) (= 2 x)) '(1 2 3)))) (should (null (list-any? (lambda (x) (= 4 x)) '(1 2 3))))) + +(ert-deftest list-duplicate () + (should (equal '() (list-duplicate 0 "hello"))) + (should (equal '("hi") (list-duplicate 1 "hi"))) + (should (equal '("bye" "bye") (list-duplicate 2 "bye"))) + (should (equal '((1 2) (1 2) (1 2)) (list-duplicate 3 '(1 2))))) + +(ert-deftest list-first () + (should (null (list-first '()))) + (should (equal 1 (list-first '() 1))) + (should (equal 1 (list-first '(1)))) + (should (equal 1 (list-first '(1) 2))) + (should (equal 1 (list-first '(1 2 3))))) + +(ert-deftest list-last () + (should (null (list-last '()))) + (should (equal 1 (list-last '() 1))) + (should (equal 1 (list-last '(1)))) + (should (equal 1 (list-last '(1) 2))) + (should (equal 3 (list-last '(1 2 3))))) + +(ert-deftest list-wrap () + (should (equal '("hello") (list-wrap "hello"))) + (should (equal '(1 2 3) (list-wrap '(1 2 3)))) + (should (equal '() (list-wrap nil)))) + +(ert-deftest list-delete () + (should (equal '(b c) (list-delete 'a '(a b c)))) + (should (equal '(a b c) (list-delete 'd '(a b c)))) + (should (equal '(a b c) (list-delete 'b '(a b b c)))) + (should (equal '() (list-delete 'b '())))) + +;; TODO(wpcarro): Supoprt this. +;; (ert-deftest list-zip () +;; (should (equal '((1 3 5) (2 4 6)) (list-zip '(1 2) '(3 4) '(5 6)))) +;; (should (equal '((1 3 5)) (list-zip '(1 2) '(3) '(5 6))))) -- cgit 1.4.1