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SketchyLISP
Reference
  Copyright (C) 2006
Nils M Holm

char-upcase

Conformance: R5RS

Purpose: Convert a char to upper case.

Arguments:
X - char

Implementation:

(define (char-upcase x)
  (cond ((char-lower-case? x)
      (integer->char (- (char->integer x) 32)))
    (#t x)))

Example:

(char-upcase #\x) 
=> #\X

See also:
char-downcase, char-upper-case?, char-alphabetic?.