Distinguish between the potentially ambiguous \nnn and the non-ambiguous \k<...> back-references

* syntax.cs (BackslashNumber): New class.
* parser.cs (ParseSpecial): Create it instead of 'Reference' if a
numeric backreference is seen.

svn path=/trunk/mcs/; revision=139656

3 files changed, 18 insertions, 1 deletions

diff --git a/mcs/class/System/System.Text.RegularExpressions/ChangeLog b/mcs/class/System/System.Text.RegularExpressions/ChangeLog
index 79707d381bf..e6e83332e02 100644
--- a/mcs/class/System/System.Text.RegularExpressions/ChangeLog
+++ b/mcs/class/System/System.Text.RegularExpressions/ChangeLog
@@ -1,5 +1,11 @@
 2009-08-10  Raja R Harinath  <harinath@hurrynot.org>
 
+	* syntax.cs (BackslashNumber): New class.
+	* parser.cs (ParseSpecial): Create it instead of 'Reference' if a
+	numeric backreference is seen.
+
+2009-08-10  Raja R Harinath  <harinath@hurrynot.org>
+
 	* parser.cs (ResolveReferences): Allow named groups to be
 	referred-to by their group numbers too.
 
diff --git a/mcs/class/System/System.Text.RegularExpressions/parser.cs b/mcs/class/System/System.Text.RegularExpressions/parser.cs
index 7cf261deb4f..ee115c17556 100644
--- a/mcs/class/System/System.Text.RegularExpressions/parser.cs
+++ b/mcs/class/System/System.Text.RegularExpressions/parser.cs
@@ -864,7 +864,7 @@ namespace System.Text.RegularExpressions.Syntax {
 				// FIXME test if number is within number of assigned groups
 				// this may present a problem for right-to-left matching
 
-				Reference reference = new Reference (IsIgnoreCase (options));
+				Reference reference = new BackslashNumber (IsIgnoreCase (options), ecma);
 				refs.Add (reference, n.ToString ());
 				expr = reference;
 				break;
diff --git a/mcs/class/System/System.Text.RegularExpressions/syntax.cs b/mcs/class/System/System.Text.RegularExpressions/syntax.cs
index 9204010c2d8..d9cc4a36141 100644
--- a/mcs/class/System/System.Text.RegularExpressions/syntax.cs
+++ b/mcs/class/System/System.Text.RegularExpressions/syntax.cs
@@ -797,6 +797,17 @@ namespace System.Text.RegularExpressions.Syntax {
 		private bool ignore;
 	}
 
+	class BackslashNumber : Reference {
+		string literal;
+		bool ecma;
+
+		public BackslashNumber (bool ignore, bool ecma)
+			: base (ignore)
+		{
+			this.ecma = ecma;
+		}
+	}
+
 	class CharacterClass : Expression {
 		public CharacterClass (bool negate, bool ignore) {
 			this.negate = negate;