--- code/trunk/study.c	2007/02/24 21:39:21	43
+++ code/trunk/study.c	2007/02/24 21:39:42	53
@@ -9,7 +9,7 @@
 
 Written by: Philip Hazel <ph10@cam.ac.uk>
 
-           Copyright (c) 1997-2000 University of Cambridge
+           Copyright (c) 1997-2001 University of Cambridge
 
 -----------------------------------------------------------------------------
 Permission is granted to anyone to use this software for any purpose on any
@@ -104,8 +104,6 @@
 
   while (try_next)
     {
-    try_next = FALSE;
-
     /* If a branch starts with a bracket or a positive lookahead assertion,
     recurse to set bits from within them. That's all for this branch. */
 
@@ -113,6 +111,7 @@
       {
       if (!set_start_bits(tcode, start_bits, caseless, cd))
         return FALSE;
+      try_next = FALSE;
       }
 
     else switch(*tcode)
@@ -120,12 +119,17 @@
       default:
       return FALSE;
 
+      /* Skip over extended extraction bracket number */
+
+      case OP_BRANUMBER:
+      tcode += 3;
+      break;
+
       /* Skip over lookbehind and negative lookahead assertions */
 
       case OP_ASSERT_NOT:
       case OP_ASSERTBACK:
       case OP_ASSERTBACK_NOT:
-      try_next = TRUE;
       do tcode += (tcode[1] << 8) + tcode[2]; while (*tcode == OP_ALT);
       tcode += 3;
       break;
@@ -135,7 +139,6 @@
       case OP_OPT:
       caseless = (tcode[1] & PCRE_CASELESS) != 0;
       tcode += 2;
-      try_next = TRUE;
       break;
 
       /* BRAZERO does the bracket, but carries on. */
@@ -147,7 +150,6 @@
       dummy = 1;
       do tcode += (tcode[1] << 8) + tcode[2]; while (*tcode == OP_ALT);
       tcode += 3;
-      try_next = TRUE;
       break;
 
       /* Single-char * or ? sets the bit and tries the next item */
@@ -158,7 +160,6 @@
       case OP_MINQUERY:
       set_bit(start_bits, tcode[1], caseless, cd);
       tcode += 2;
-      try_next = TRUE;
       break;
 
       /* Single-char upto sets the bit and tries the next */
@@ -167,7 +168,6 @@
       case OP_MINUPTO:
       set_bit(start_bits, tcode[3], caseless, cd);
       tcode += 4;
-      try_next = TRUE;
       break;
 
       /* At least one single char sets the bit and stops */
@@ -181,6 +181,7 @@
       case OP_PLUS:
       case OP_MINPLUS:
       set_bit(start_bits, tcode[1], caseless, cd);
+      try_next = FALSE;
       break;
 
       /* Single character type sets the bits and stops */
@@ -188,31 +189,37 @@
       case OP_NOT_DIGIT:
       for (c = 0; c < 32; c++)
         start_bits[c] |= ~cd->cbits[c+cbit_digit];
+      try_next = FALSE;
       break;
 
       case OP_DIGIT:
       for (c = 0; c < 32; c++)
         start_bits[c] |= cd->cbits[c+cbit_digit];
+      try_next = FALSE;
       break;
 
       case OP_NOT_WHITESPACE:
       for (c = 0; c < 32; c++)
         start_bits[c] |= ~cd->cbits[c+cbit_space];
+      try_next = FALSE;
       break;
 
       case OP_WHITESPACE:
       for (c = 0; c < 32; c++)
         start_bits[c] |= cd->cbits[c+cbit_space];
+      try_next = FALSE;
       break;
 
       case OP_NOT_WORDCHAR:
       for (c = 0; c < 32; c++)
         start_bits[c] |= ~cd->cbits[c+cbit_word];
+      try_next = FALSE;
       break;
 
       case OP_WORDCHAR:
       for (c = 0; c < 32; c++)
         start_bits[c] |= cd->cbits[c+cbit_word];
+      try_next = FALSE;
       break;
 
       /* One or more character type fudges the pointer and restarts, knowing
@@ -221,12 +228,10 @@
       case OP_TYPEPLUS:
       case OP_TYPEMINPLUS:
       tcode++;
-      try_next = TRUE;
       break;
 
       case OP_TYPEEXACT:
       tcode += 3;
-      try_next = TRUE;
       break;
 
       /* Zero or more repeats of character types set the bits and then
@@ -274,7 +279,6 @@
         }
 
       tcode += 2;
-      try_next = TRUE;
       break;
 
       /* Character class: set the bits and either carry on or not,
@@ -292,16 +296,16 @@
           case OP_CRQUERY:
           case OP_CRMINQUERY:
           tcode++;
-          try_next = TRUE;
           break;
 
           case OP_CRRANGE:
           case OP_CRMINRANGE:
-          if (((tcode[1] << 8) + tcode[2]) == 0)
-            {
-            tcode += 5;
-            try_next = TRUE;
-            }
+          if (((tcode[1] << 8) + tcode[2]) == 0) tcode += 5;
+            else try_next = FALSE;
+          break;
+
+          default:
+          try_next = FALSE;
           break;
           }
         }