Add commentary; nfc.

ice-9/regex.scm

@@ -39,6 +39,26 @@
 ;;;; whether to permit this exception to apply to your modifications.
 ;;;; If you do not wish that, delete this exception notice.
 ;;;;
+
+;;; Commentary:
+
+;; These procedures are exported:
+;;  (match:count match)
+;;  (match:string match)
+;;  (match:prefix match)
+;;  (match:suffix match)
+;;  (regexp-match? match)
+;;  (regexp-quote string)
+;;  (match:start match . submatch-num)
+;;  (match:end match . submatch-num)
+;;  (match:substring match . submatch-num)
+;;  (string-match pattern str . start)
+;;  (regexp-substitute port match . items)
+;;  (fold-matches regexp string init proc . flags)
+;;  (list-matches regexp string . flags)
+;;  (regexp-substitute/global port regexp string . items)
+
+;;; Code:
 
 ;;;; POSIX regex support functions.
 
@@ -83,16 +103,16 @@
 		(loop (+ 1 i)))
 	       (else #f)))))
 
-(define (regexp-quote regexp)
+(define (regexp-quote string)
   (call-with-output-string
    (lambda (p)
      (let loop ((i 0))
-       (and (< i (string-length regexp))
+       (and (< i (string-length string))
 	    (begin
-	      (case (string-ref regexp i)
+	      (case (string-ref string i)
 		((#\* #\. #\( #\) #\+ #\? #\\ #\^ #\$ #\{ #\})
 		 (write-char #\\ p)))
-	      (write-char (string-ref regexp i) p)
+	      (write-char (string-ref string i) p)
 	      (loop (1+ i))))))))
 
 (define (match:start match . args)