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SketchyLISP
Reference
  Copyright (C) 2007
Nils M Holm

char-numeric?

Conformance: R5RS Scheme

Purpose: Test whether a char is numeric.

Arguments:
X - char

Implementation:

(define (char-numeric? x)
  (and (char<=? #\0 x)
       (char<=? x #\9)))

Example:

(char-numeric? #\5) 
=> #t

See also:
char-lower-case?, char-alphabetic?, char-whitespace?.