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SketchyLISP
Reference
  Copyright (C) 2006
Nils M Holm

char-ci<=?

Conformance: R5RS

Purpose: Case-insensitively test whether two chars are in lexically non-descending order.

Arguments:
X - char
Y - char

Implementation:

(define (char-ci<=? x y)
  (eq? (char-ci>? x y) #f))

Example:

(char-ci<=? #\b #\B) 
=> #t

See also:
char<=?, char-ci<?, char-ci=?, char-ci>?, char-ci>=?, string<=?, equal?.