mes/mes/module/srfi/srfi-14.mes

91 lines
3.1 KiB
Scheme

;;; -*-scheme-*-
;;; GNU Mes --- Maxwell Equations of Software
;;; Copyright © 2016,2018 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
;;;
;;; This file is part of GNU Mes.
;;;
;;; GNU Mes 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 Mes 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 Mes. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;;; Minimal implementation of srfi-14, for nyacc.
;;; Code:
;; FIXME: have structs
(define (char-set . x)
(cons '*char-set* x))
(define (char-set? x)
(and (pair? x) (eq? (car x) '*char-set*)))
(define (char-set= a b)
(and (char-set? a) (char-set? b)
(equal? a b)))
(define char-set:whitespace (char-set #\tab #\page #\return #\vtab #\newline #\space))
(define char-set:digit (apply char-set
(map integer->char
(map (lambda (i)
(+ i (char->integer #\0))) (iota 10)))))
(define char-set:lower-case (apply char-set
(map integer->char
(map (lambda (i)
(+ i (char->integer #\a))) (iota 26)))))
(define char-set:upper-case (apply char-set
(map integer->char
(map (lambda (i)
(+ i (char->integer #\A))) (iota 26)))))
(define (list->char-set lst)
(apply char-set lst))
(define (string->char-set x . base)
(apply char-set (append (string->list x) (if (null? base) '() (cdar base)))))
(define (string->char-set! x base)
(set-cdr! (last-pair base) (string->list x))
base)
(define (char-set-adjoin cs . chars)
(append cs chars))
(define (char-set-contains? cs x)
(and (memq x cs) #t))
(define (char-set-complement cs)
(let ((ascii (map integer->char (iota 128))))
(list->char-set (filter (lambda (c) (not (char-set-contains? cs c))) ascii))))
(define (char-whitespace? c)
(char-set-contains? char-set:whitespace c))
(define (char-set-copy cs)
(map identity cs))
(define (char-upcase c)
(if (char-set-contains? char-set:lower-case c) (integer->char (- (char->integer c)
(- (char->integer #\a)
(char->integer #\A))))
c))
(define (char-downcase c)
(if (char-set-contains? char-set:upper-case c) (integer->char (+ (char->integer c)
(- (char->integer #\a)
(char->integer #\A))))
c))