cyclone/scheme/char.sld
2016-10-15 18:19:18 -04:00

79 lines
2.9 KiB
Scheme

;;;; Cyclone Scheme
;;;; https://github.com/justinethier/cyclone
;;;;
;;;; Copyright (c) 2014-2016, Justin Ethier
;;;; All rights reserved.
;;;;
;;;; This module contains the char library from r7rs.
;;;;
(define-library (scheme char)
(export
char-alphabetic?
char-downcase
char-foldcase
char-lower-case?
char-numeric?
char-upcase
char-upper-case?
char-whitespace?
char-ci<=?
char-ci<?
char-ci=?
char-ci>=?
char-ci>?
digit-value
string-upcase
string-downcase
string-foldcase
string-ci<=?
string-ci<?
string-ci=?
string-ci>=?
string-ci>?
)
(import (scheme base))
(begin
(define (char-upcase c) ;; ASCII-only
(if (char-lower-case? c)
(integer->char
(- (char->integer c)
(- (char->integer #\a)
(char->integer #\A))))
c))
(define (char-downcase c) ;; ASCII-only
(if (char-upper-case? c)
(integer->char
(+ (char->integer c)
(- (char->integer #\a)
(char->integer #\A))))
c))
(define char-foldcase char-downcase) ;; Good enough for now, since no Unicode yet
(define (char-ci=? c1 c2 . cs) (apply char=? (map char-foldcase (cons c1 (cons c2 cs)))))
(define (char-ci<=? c1 c2 . cs) (apply char<=? (map char-foldcase (cons c1 (cons c2 cs)))))
(define (char-ci<? c1 c2 . cs) (apply char<? (map char-foldcase (cons c1 (cons c2 cs)))))
(define (char-ci>=? c1 c2 . cs) (apply char>=? (map char-foldcase (cons c1 (cons c2 cs)))))
(define (char-ci>? c1 c2 . cs) (apply char>? (map char-foldcase (cons c1 (cons c2 cs)))))
(define (string-ci=? s1 s2) (apply string=? (map string-foldcase (list s1 s2))))
(define (string-ci<? s1 s2) (apply string<? (map string-foldcase (list s1 s2))))
(define (string-ci<=? s1 s2) (apply string<=? (map string-foldcase (list s1 s2))))
(define (string-ci>? s1 s2) (apply string>? (map string-foldcase (list s1 s2))))
(define (string-ci>=? s1 s2) (apply string>=? (map string-foldcase (list s1 s2))))
(define (char-alphabetic? c) (or (char-upper-case? c) (char-lower-case? c)))
(define (char-upper-case? c) (and (char>=? c #\A) (char<=? c #\Z))) ;; ASCII-only
(define (char-lower-case? c) (and (char>=? c #\a) (char<=? c #\z))) ;; ASCII-only
(define (char-numeric? c)
(if (Cyc-fast-member c '(#\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7 #\8 #\9))
#t
#f))
(define (char-whitespace? c)
(if (Cyc-fast-member c '(#\tab #\space #\return #\newline))
#t
#f))
(define (digit-value c)
(if (char-numeric? c)
(- (char->integer c) (char->integer #\0))
#f))
(define (string-upcase str) (string-map char-upcase str))
(define (string-downcase str) (string-map char-downcase str))
(define (string-foldcase str) (string-map char-foldcase str))
))