class Parser::Builders::Default

def pair_keyword_map(key_t, value_e) 

def pair_keyword_map(key_t, value_e)
  key_range = loc(key_t)
  key_l   = Source::Range.new(key_range.source_buffer,
                              key_range.begin_pos,
                              key_range.end_pos - 1)
  colon_l = Source::Range.new(key_range.source_buffer,
                              key_range.end_pos - 1,
                              key_range.end_pos)
    # key map
  [ Source::Map::Collection.new(nil, nil,
                                key_l),
    # pair map
    Source::Map::Operator.new(colon_l,
                              key_range.join(value_e.loc.expression)) ]
end