From 334ece1ee77c7d76a8fec046681b2f4a817685a9 Mon Sep 17 00:00:00 2001 From: Aryadev Chavali Date: Fri, 14 Feb 2025 21:46:15 +0000 Subject: Split source code into different modules for cleanliness --- lib/functions.lisp | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 lib/functions.lisp (limited to 'lib/functions.lisp') diff --git a/lib/functions.lisp b/lib/functions.lisp new file mode 100644 index 0000000..99796c9 --- /dev/null +++ b/lib/functions.lisp @@ -0,0 +1,56 @@ +;;; lib.functions.lisp - 2025-02-09 + +;; Copyright (C) 2025 Aryadev Chavali + +;; 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 Version 2 for +;; details. + +;; You may distribute and modify this code under the terms of the GNU General +;; Public License Version 2, which you should have received a copy of along with +;; this program. If not, please go to . + +;;; Commentary: + +;; Helpful functions for usage throughout the project. + +;;; Code: + +(in-package :cantedraw.lib.functions) + +(fn range (start end &optional (step 1)) (-> (fixnum fixnum &optional fixnum) list) + "Make a list of numbers from START to END (exclusive). If STEP is given, then +each member is STEP distance apart." + (if (<= end start) + (error (format nil "~a < ~a" end start)) + (loop :for i :from start :to (1- end) :by step + :collect i))) + +(fn take (n lst) (-> (fixnum list) list) + "Return the first N elements of LST." + (subseq lst 0 n)) + +(fn split (n lst) (-> (fixnum list) list) + "Return CONS where CAR is the first N elements of LST and CDR is the rest." + (cons (take n lst) + (subseq lst n))) + +(fn rev-map (indicator lst &key (key-eq #'eq)) + (-> (function list &key (:key-eq function)) list) + "Given LST and INDICATOR: LST -> A, return an association list A -> 2^LST +where key x in A has associations {y in LST : INDICATOR(y) = x}." + (loop :with assoc-list := nil + :for element :in lst + :for key := (funcall indicator element) + :if (assoc key assoc-list :test key-eq) + :do (->> (alist-val key assoc-list) + (cons element) + (setf (alist-val key assoc-list))) + :else + :do (setq assoc-list (cons (list key element) assoc-list)) + :finally (return assoc-list))) + +(fn parse-integer* (inp) (-> (string) (or integer list)) + "Given string INP, attempt to parse an integer. Return NIL otherwise." + (parse-integer inp :junk-allowed t)) -- cgit v1.2.3-13-gbd6f