diff options
| -rw-r--r-- | configs/shared/.emacs.d/wpc/alist.el | 51 |
1 files changed, 50 insertions, 1 deletions
diff --git a/configs/shared/.emacs.d/wpc/alist.el b/configs/shared/.emacs.d/wpc/alist.el index da0ce68b8f75..c43df7823b32 100644 --- a/configs/shared/.emacs.d/wpc/alist.el +++ b/configs/shared/.emacs.d/wpc/alist.el @@ -85,6 +85,17 @@ ;; TODO: Consider wrapping all of this with `(cl-defstruct alist xs)'. +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;; Constants +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(defconst alist/enable-tests? t + "When t, run the test suite.") + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;; Library +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + (defun alist/new () "Return a new, empty alist." '()) @@ -181,8 +192,29 @@ Mutative variant of `alist/delete'." "Return the number of entries in XS." (length xs)) +;; TODO: Should I support `alist/find-key' and `alist/find-value' variants? +(defun alist/find (p xs) + "Apply a predicate fn, P, to each key and value in XS and return the key of + the first element that returns t." + (let ((result (list/find (lambda (x) (funcall p (car x) (cdr x))) xs))) + (if result + (car result) + nil))) + +(defun alist/map-keys (f xs) + "Call F on the values in XS, returning a new alist." + (list/map (lambda (x) + `(,(funcall f (car x)) . ,(cdr x))) + xs)) + +(defun alist/map-values (f xs) + "Call F on the values in XS, returning a new alist." + (list/map (lambda (x) + `(,(car x) . ,(funcall f (cdr x)))) + xs)) + (defun alist/reduce (acc f xs) - "Return a new alist by calling, F, on k v and ACC from XS. + "Return a new alist by calling F on k v and ACC from XS. F should return a tuple. See tuple.el for more information." (->> (alist/keys xs) (list/reduce acc @@ -219,7 +251,24 @@ In this case, the last writer wins, which is B." (alist/dedupe-entries person) (alist/count person))) +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Tests +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; + +(when alist/enable-tests? + (prelude/assert + (equal '((2 . one) + (3 . two)) + (alist/map-keys #'1+ + '((1 . one) + (2 . two))))) + (prelude/assert + (equal '((one . 2) + (two . 3)) + (alist/map-values #'1+ + '((one . 1) + (two . 2)))))) + ;; TODO: Support test cases for the entire API. |