From dce89b2fa8885c4613763b3f765fc061028798ba Mon Sep 17 00:00:00 2001
From: sperber <sperber>
Date: Fri, 22 Feb 2002 10:22:38 +0000
Subject: [PATCH] Translate submatches according to CRE:TVEC, fixing submatch
 bug reported by Michel Schinz.

---
 scsh/rx/re-low.scm | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/scsh/rx/re-low.scm b/scsh/rx/re-low.scm
index aa33ac2..a138ae7 100644
--- a/scsh/rx/re-low.scm
+++ b/scsh/rx/re-low.scm
@@ -83,7 +83,29 @@
 	    (if (not ret)
 		#f
 		(make-regexp-match str 
-				   (list->vector ret))))))))
+				   (translate-submatches ret
+							 (cre:tvec cre)
+							 start-vec))))))))
+
+(define (translate-submatches matches trans-vec match-vec)
+  (let ((n-virtual-submatches (vector-length trans-vec)))
+    (let loop ((virtual-index 0)
+	       (match-index 0)
+	       (matches matches))
+      (cond
+       ((> virtual-index n-virtual-submatches)
+	match-vec)
+       ((if (zero? virtual-index)
+	    0
+	    (vector-ref trans-vec (- virtual-index 1)))
+	=> (lambda (actual-index)
+	     (if (= match-index actual-index)
+		 (begin
+		   (vector-set! match-vec virtual-index (car matches))
+		   (loop (+ 1 virtual-index) (+ 1 match-index) (cdr matches)))
+		 (loop virtual-index (+ 1 match-index) (cdr matches)))))
+       (else
+	(loop (+ 1 virtual-index) match-index matches))))))
 
 (define (cre-search? cre str start)
   (let ((re-str (cre:string cre)))	;; RE-STR = #F => empty match.