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Diffstat (limited to 'configs/shared/emacs/.emacs.d/elpa/let-alist-1.0.5/let-alist.el')
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diff --git a/configs/shared/emacs/.emacs.d/elpa/let-alist-1.0.5/let-alist.el b/configs/shared/emacs/.emacs.d/elpa/let-alist-1.0.5/let-alist.el new file mode 100644 index 000000000000..43973c26cda3 --- /dev/null +++ b/configs/shared/emacs/.emacs.d/elpa/let-alist-1.0.5/let-alist.el @@ -0,0 +1,182 @@ +;;; let-alist.el --- Easily let-bind values of an assoc-list by their names -*- lexical-binding: t; -*- + +;; Copyright (C) 2014-2017 Free Software Foundation, Inc. + +;; Author: Artur Malabarba <emacs@endlessparentheses.com> +;; Package-Requires: ((emacs "24.1")) +;; Version: 1.0.5 +;; Keywords: extensions lisp +;; Prefix: let-alist +;; Separator: - + +;; This is an Elpa :core package. Don't use functionality that is not +;; compatible with Emacs 24.1. + +;; This file is part of GNU Emacs. + +;; GNU Emacs 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. + +;; GNU Emacs 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 GNU Emacs. If not, see <http://www.gnu.org/licenses/>. + +;;; Commentary: + +;; This package offers a single macro, `let-alist'. This macro takes a +;; first argument (whose value must be an alist) and a body. +;; +;; The macro expands to a let form containing body, where each dotted +;; symbol inside body is let-bound to their cdrs in the alist. Dotted +;; symbol is any symbol starting with a `.'. Only those present in +;; the body are let-bound and this search is done at compile time. +;; +;; For instance, the following code +;; +;; (let-alist alist +;; (if (and .title .body) +;; .body +;; .site +;; .site.contents)) +;; +;; essentially expands to +;; +;; (let ((.title (cdr (assq 'title alist))) +;; (.body (cdr (assq 'body alist))) +;; (.site (cdr (assq 'site alist))) +;; (.site.contents (cdr (assq 'contents (cdr (assq 'site alist)))))) +;; (if (and .title .body) +;; .body +;; .site +;; .site.contents)) +;; +;; If you nest `let-alist' invocations, the inner one can't access +;; the variables of the outer one. You can, however, access alists +;; inside the original alist by using dots inside the symbol, as +;; displayed in the example above by the `.site.contents'. +;; +;;; Code: + + +(defun let-alist--deep-dot-search (data) + "Return alist of symbols inside DATA that start with a `.'. +Perform a deep search and return an alist where each car is the +symbol, and each cdr is the same symbol without the `.'." + (cond + ((symbolp data) + (let ((name (symbol-name data))) + (when (string-match "\\`\\." name) + ;; Return the cons cell inside a list, so it can be appended + ;; with other results in the clause below. + (list (cons data (intern (replace-match "" nil nil name))))))) + ((not (consp data)) nil) + ((eq (car data) 'let-alist) + ;; For nested ‘let-alist’ forms, ignore symbols appearing in the + ;; inner body because they don’t refer to the alist currently + ;; being processed. See Bug#24641. + (let-alist--deep-dot-search (cadr data))) + (t (append (let-alist--deep-dot-search (car data)) + (let-alist--deep-dot-search (cdr data)))))) + +(defun let-alist--access-sexp (symbol variable) + "Return a sexp used to access SYMBOL inside VARIABLE." + (let* ((clean (let-alist--remove-dot symbol)) + (name (symbol-name clean))) + (if (string-match "\\`\\." name) + clean + (let-alist--list-to-sexp + (mapcar #'intern (nreverse (split-string name "\\."))) + variable)))) + +(defun let-alist--list-to-sexp (list var) + "Turn symbols LIST into recursive calls to `cdr' `assq' on VAR." + `(cdr (assq ',(car list) + ,(if (cdr list) (let-alist--list-to-sexp (cdr list) var) + var)))) + +(defun let-alist--remove-dot (symbol) + "Return SYMBOL, sans an initial dot." + (let ((name (symbol-name symbol))) + (if (string-match "\\`\\." name) + (intern (replace-match "" nil nil name)) + symbol))) + + +;;; The actual macro. +;;;###autoload +(defmacro let-alist (alist &rest body) + "Let-bind dotted symbols to their cdrs in ALIST and execute BODY. +Dotted symbol is any symbol starting with a `.'. Only those present +in BODY are let-bound and this search is done at compile time. + +For instance, the following code + + (let-alist alist + (if (and .title .body) + .body + .site + .site.contents)) + +essentially expands to + + (let ((.title (cdr (assq \\='title alist))) + (.body (cdr (assq \\='body alist))) + (.site (cdr (assq \\='site alist))) + (.site.contents (cdr (assq \\='contents (cdr (assq \\='site alist)))))) + (if (and .title .body) + .body + .site + .site.contents)) + +If you nest `let-alist' invocations, the inner one can't access +the variables of the outer one. You can, however, access alists +inside the original alist by using dots inside the symbol, as +displayed in the example above." + (declare (indent 1) (debug t)) + (let ((var (make-symbol "alist"))) + `(let ((,var ,alist)) + (let ,(mapcar (lambda (x) `(,(car x) ,(let-alist--access-sexp (car x) var))) + (delete-dups (let-alist--deep-dot-search body))) + ,@body)))) + +;;;; ChangeLog: + +;; 2015-12-01 Artur Malabarba <bruce.connor.am@gmail.com> +;; +;; packages/let-alist: Define it as a :core package +;; +;; 2015-06-11 Artur Malabarba <bruce.connor.am@gmail.com> +;; +;; * let-alist (let-alist--deep-dot-search): Fix cons +;; +;; 2015-03-07 Artur Malabarba <bruce.connor.am@gmail.com> +;; +;; let-alist: Update copyright +;; +;; 2014-12-22 Artur Malabarba <bruce.connor.am@gmail.com> +;; +;; packages/let-alist: Use `make-symbol' instead of `gensym'. +;; +;; 2014-12-20 Artur Malabarba <bruce.connor.am@gmail.com> +;; +;; packages/let-alist: Enable access to deeper alists +;; +;; 2014-12-14 Artur Malabarba <bruce.connor.am@gmail.com> +;; +;; let-alist.el: Add lexical binding. Version bump. +;; +;; 2014-12-11 Artur Malabarba <bruce.connor.am@gmail.com> +;; +;; let-alist: New package +;; + + +(provide 'let-alist) + +;;; let-alist.el ends here |