reorganization of switch in function 'match' (details)

lstrlib.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lstrlib.c,v 1.146 2009/12/17 12:26:09 roberto Exp roberto $
+** $Id: lstrlib.c,v 1.147 2009/12/17 12:50:20 roberto Exp roberto $
 ** Standard library for string operations and pattern-matching
 ** See Copyright Notice in lua.h
 */
@@ -384,7 +384,15 @@ static const char *match (MatchState *ms, const char *s, const char *p) {
     case ')': {  /* end capture */
       return end_capture(ms, s, p+1);
     }
-    case L_ESC: {
+    case '\0': {  /* end of pattern */
+      return s;  /* match succeeded */
+    }
+    case '$': {
+      if (*(p+1) == '\0')  /* is the `$' the last char in pattern? */
+        return (s == ms->src_end) ? s : NULL;  /* check end of string */
+      else goto dflt;
+    }
+    case L_ESC: {  /* escaped sequences not in the format class[*+?-]? */
       switch (*(p+1)) {
         case 'b': {  /* balanced string? */
           s = matchbalance(ms, s, p+2);
@@ -403,25 +411,17 @@ static const char *match (MatchState *ms, const char *s, const char *p) {
              !matchbracketclass(uchar(*s), p, ep-1)) return NULL;
           p=ep; goto init;  /* else return match(ms, s, ep); */
         }
-        default: {
-          if (isdigit(uchar(*(p+1)))) {  /* capture results (%0-%9)? */
-            s = match_capture(ms, s, uchar(*(p+1)));
-            if (s == NULL) return NULL;
-            p+=2; goto init;  /* else return match(ms, s, p+2) */
-          }
-          goto dflt;  /* case default */
+        case '0': case '1': case '2': case '3':
+        case '4': case '5': case '6': case '7':
+        case '8': case '9': {  /* capture results (%0-%9)? */
+          s = match_capture(ms, s, uchar(*(p+1)));
+          if (s == NULL) return NULL;
+          p+=2; goto init;  /* else return match(ms, s, p+2) */
         }
+        default: break;  /* go through to 'dflt' */
       }
     }
-    case '\0': {  /* end of pattern */
-      return s;  /* match succeeded */
-    }
-    case '$': {
-      if (*(p+1) == '\0')  /* is the `$' the last char in pattern? */
-        return (s == ms->src_end) ? s : NULL;  /* check end of string */
-      else goto dflt;
-    }
-    default: dflt: {  /* it is a pattern item */
+    default: dflt: {  /* pattern class plus optional sufix */
       const char *ep = classend(ms, p);  /* points to what is next */
       int m = s<ms->src_end && singlematch(uchar(*s), p, ep);
       switch (*ep) {