Changing submatching syntax from "->" to ":" and M, MA to be shorthand for...

Changing submatching syntax from "->" to ":"  and M, MA to be shorthand for ($m:_M):1 and ($m:_M):2, respectively.
Also, "M" is optional if followed by ":", "M:1" is same as ":1"

libwccl/parser/grammar.g

@@ -2299,11 +2299,18 @@ match_fit
 }
 	:
 	( ret = match_var_val [tagset, vars]
-	| "M" { ret.reset(new VarGetter<Match>(vars.create_accessor<Match>("_M")));	}
+	| {LA(1)==LITERAL_M || LA(1)==COLON}? ("M")? {
+			ret.reset(new VarGetter<Match>(vars.create_accessor<Match>("_M")));
+			ret.reset(new Submatch(ret, 1));
+		}
+	| "MA" { 
+			ret.reset(new VarGetter<Match>(vars.create_accessor<Match>("_M")));
+			ret.reset(new Submatch(ret, 2));
+		}
 	| LPAREN ret = match_fit [tagset, vars] RPAREN
 	)
 	( // if there's an arrow after the match, we have a submatch reference
-		ARROW i: UNSIGNED_INT { ret.reset(new Submatch(ret, token_ref_to_int(i))); }
+		COLON i: UNSIGNED_INT { ret.reset(new Submatch(ret, token_ref_to_int(i))); }
 	)*
 ;
 
@@ -2478,6 +2485,13 @@ options {
 	: "->"
 ;
 
+COLON
+options {
+	paraphrase = ":";
+}
+	: ':'
+;
+
 SYMBOL
 options { 
 	paraphrase = "Symbol";