# File lib/ruby19_parser.rb, line 5155
def _reduce_401(val, _values, result)
                      # TODO:
                      # if (nd_type($1) == NODE_YIELD) {
                      #     compile_error(PARSER_ARG "block given to yield");

                      syntax_error "Both block arg and actual block given." if
                        val[0].block_pass?

                      result = val[1]
                      result.insert 1, val[0]
                    
    result
end