mutable decl syntax change

testbed/lexer/main.bro

@@ -48,7 +48,7 @@ hide append_token func(tokens @mut std.ArrayList(Token), kind Kind, start, end u
 }
 
 lex func(source []u8, tokens @mut std.ArrayList(Token)) void ! mem.AllocError {
-	cursor usize = 0
+	cursor usize := 0
 	while cursor < source.len {
 		value u8 :: source[cursor]
 		if value == ' ' or value == '\t' or value == '\r' {
@@ -112,7 +112,7 @@ hide print_token func(source []u8, token Token) void {
 	_ = c.printf("%-11s", kind_name(token.kind))
 	if token.length != 0 {
 		_ = c.printf(" `")
-		i usize = 0
+		i usize := 0
 		while i < token.length : i += 1 {
 			value u8 :: source[token.start + i]
 			if value == '\n' {
@@ -132,7 +132,7 @@ main func() i32 {
 		`   hello()
 		`}
 
-	tokens std.ArrayList(Token) = arraylist.init(mem.c_allocator)
+	tokens std.ArrayList(Token) := arraylist.init(mem.c_allocator)
 	defer arraylist.deinit(&tokens)
 
 	lex(source, &tokens) catch |_| {