repl-substring?

Description

Returns #t if target occurs at pos in string.

Author

Norman Walsh, <ndw@nwalsh.com>

Source Code

(define (repl-substring? string target pos)
  ;; Returns true if the specified substring can be replaced
  (let* ((could-match (<= (+ pos (string-length target)) 
			 (string-length string)))
	 (match (if could-match 
		    (substring string pos (+ pos (string-length target))) "")))
    (and could-match (string=? match target))))