Pass lexer state explicitly

boot/stage19/cl.elna

@@ -8,6 +8,7 @@ program;
 (* Stage 19 compiler. *)
 
 (* - Aggregates can be allocated on the stack. *)
+(* - Procedure return type is parsed. *)
 
 type
 	(**
@@ -3565,7 +3566,9 @@ begin
 	_elna_lexer_skip_token();
 
 	if token_kind = ElnaLexerKind.arrow then
-		result^.return_type := elna_parser_type_expression()
+		result^.return_type := elna_parser_type_expression();
+		_elna_lexer_read_token(@token_kind);
+		_elna_lexer_skip_token()
 	else
 		result^.return_type := nil
 	end;