Added Anchor() regex (so that we're not just using Alphanumeric to match anchors), but it's still not 100% right (it shouldn't allow non-printable characters, e.g.). Also fixed a test that was broken along these lines (if a colon immediately follows an anchor, it's part of the anchor)

src/exp.h

@@ -112,6 +112,10 @@ namespace YAML
 			static const RegEx e = RegEx('#');
 			return e;
 		}
+		inline const RegEx& Anchor() {
+			static const RegEx e = !(RegEx("[]{},", REGEX_OR) || BlankOrBreak());
+			return e;
+		}
 		inline const RegEx& AnchorEnd() {
 			static const RegEx e = RegEx("?:,]}%@`", REGEX_OR) || BlankOrBreak();
 			return e;

src/scantoken.cpp

@@ -238,7 +238,7 @@ namespace YAML
 		alias = (indicator == Keys::Alias);
 
 		// now eat the content
-		while(Exp::AlphaNumeric().Matches(INPUT))
+		while(INPUT && Exp::Anchor().Matches(INPUT))
 			name += INPUT.get();
 
 		// we need to have read SOMETHING!

test/parsertests.cpp

@@ -472,7 +472,7 @@ namespace Test
 		
 		bool AliasAsSimpleKey()
 		{
-			std::string input = "- &a b\n- *a: c";
+			std::string input = "- &a b\n- *a : c";
 			
 			std::stringstream stream(input);
 			YAML::Parser parser(stream);