[vala] Do not create empty type parameter lists in parser

[Jürg Billeter <juergbi src gnome org>]

commit d3281263e9d81f912c253d8a06a95c4bbc46cc22
Author: Jürg Billeter <j bitron ch>
Date:   Sat Aug 21 12:11:58 2010 +0200

    Do not create empty type parameter lists in parser

 vala/valaparser.vala |   11 +++++++++--
 1 files changed, 9 insertions(+), 2 deletions(-)
---
diff --git a/vala/valaparser.vala b/vala/valaparser.vala
index 04f0d59..f05c15f 100644
--- a/vala/valaparser.vala
+++ b/vala/valaparser.vala
@@ -41,6 +41,8 @@ public class Vala.Parser : CodeVisitor {
 
 	const int BUFFER_SIZE = 32;
 
+	static List<TypeParameter> _empty_type_parameter_list;
+
 	struct TokenInfo {
 		public TokenType type;
 		public SourceLocation begin;
@@ -3293,16 +3295,21 @@ public class Vala.Parser : CodeVisitor {
 	}
 
 	List<TypeParameter> parse_type_parameter_list () throws ParseError {
-		var list = new ArrayList<TypeParameter> ();
 		if (accept (TokenType.OP_LT)) {
+			var list = new ArrayList<TypeParameter> ();
 			do {
 				var begin = get_location ();
 				string id = parse_identifier ();
 				list.add (new TypeParameter (id, get_src (begin)));
 			} while (accept (TokenType.COMMA));
 			expect (TokenType.OP_GT);
+			return list;
+		} else {
+			if (_empty_type_parameter_list == null) {
+				_empty_type_parameter_list = new ArrayList<TypeParameter> ();
+			}
+			return _empty_type_parameter_list;
 		}
-		return list;
 	}
 
 	void skip_type_argument_list () throws ParseError {