ff8277625f
This was a doozey because I use it everywhere. Is there a better way to globally rename things? Aye aye aye... computers, man!
88 lines
3.1 KiB
EmacsLisp
88 lines
3.1 KiB
EmacsLisp
;;; struct.el --- Helpers for working with structs -*- lexical-binding: t -*-
|
|
;; Author: William Carroll <wpcarro@gmail.com>
|
|
|
|
;;; Commentary:
|
|
;; Provides new macros for working with structs. Also provides adapter
|
|
;; interfaces to existing struct macros, that should have more intuitive
|
|
;; interfaces.
|
|
;;
|
|
;; Sometimes `setf' just isn't enough.
|
|
|
|
;;; Code:
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; Wish list
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
;; - TODO: Replace `symbol-name' and `intern' calls with isomorphism.
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; Dependencies
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
(require 'string)
|
|
(require 'dash)
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; Library
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
(defvar struct/enable-tests? t
|
|
"When t, run the test suite defined herein.")
|
|
|
|
(defmacro struct/update (type field f xs)
|
|
"Apply F to FIELD in XS, which is a struct of TYPE.
|
|
This is immutable."
|
|
(let ((copier (->> type
|
|
symbol-name
|
|
(string/prepend "copy-")
|
|
intern))
|
|
(accessor (->> field
|
|
symbol-name
|
|
(string/prepend (string/concat (symbol-name type) "-"))
|
|
intern)))
|
|
`(let ((copy (,copier ,xs)))
|
|
(setf (,accessor copy) (funcall ,f (,accessor copy)))
|
|
copy)))
|
|
|
|
(defmacro struct/set (type field x xs)
|
|
"Immutably set FIELD in XS (struct TYPE) to X."
|
|
(let ((copier (->> type
|
|
symbol-name
|
|
(string/prepend "copy-")
|
|
intern))
|
|
(accessor (->> field
|
|
symbol-name
|
|
(string/prepend (string/concat (symbol-name type) "-"))
|
|
intern)))
|
|
`(let ((copy (,copier ,xs)))
|
|
(setf (,accessor copy) ,x)
|
|
copy)))
|
|
|
|
(defmacro struct/set! (type field x xs)
|
|
"Set FIELD in XS (struct TYPE) to X mutably.
|
|
This is an adapter interface to `setf'."
|
|
(let ((accessor (->> field
|
|
symbol-name
|
|
(string/prepend (string/concat (symbol-name type) "-"))
|
|
intern)))
|
|
`(progn
|
|
(setf (,accessor ,xs) ,x)
|
|
,xs)))
|
|
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
;; Tests
|
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
|
|
|
(when struct/enable-tests?
|
|
(cl-defstruct dummy name age)
|
|
(defvar test-dummy (make-dummy :name "Roofus" :age 19))
|
|
(struct/set! dummy name "Doofus" test-dummy)
|
|
(prelude-assert (string= "Doofus" (dummy-name test-dummy)))
|
|
(let ((result (struct/set dummy name "Shoofus" test-dummy)))
|
|
;; Test the immutability of `struct/set'
|
|
(prelude-assert (string= "Doofus" (dummy-name test-dummy)))
|
|
(prelude-assert (string= "Shoofus" (dummy-name result)))))
|
|
|
|
(provide 'struct)
|
|
;;; struct.el ends here
|