SOURCE_FILE
  USE
    USE_KW "use"
    WHITESPACE " "
    USE_TREE
      PATH
        PATH_SEGMENT
          NAME_REF
            IDENT "std"
      COLON2 "::"
      USE_TREE_LIST
        L_CURLY "{"
        USE_TREE
          PATH
            PATH
              PATH_SEGMENT
                NAME_REF
                  IDENT "error"
            COLON2 "::"
            PATH_SEGMENT
              NAME_REF
                IDENT "Error"
        ERROR
          SEMICOLON ";"
        WHITESPACE "\n"
        ERROR
          USE_KW "use"
        WHITESPACE " "
        USE_TREE
          PATH
            PATH
              PATH_SEGMENT
                NAME_REF
                  IDENT "std"
            COLON2 "::"
            PATH_SEGMENT
              NAME_REF
                IDENT "io"
        ERROR
          SEMICOLON ";"
  WHITESPACE "\n"
error 22: expected COMMA
error 22: expected one of `*`, `::`, `{`, `self`, `super` or an identifier
error 23: expected COMMA
error 24: expected one of `*`, `::`, `{`, `self`, `super` or an identifier
error 27: expected COMMA
error 35: expected COMMA
error 35: expected one of `*`, `::`, `{`, `self`, `super` or an identifier
error 36: expected COMMA
error 36: expected R_CURLY
error 36: expected SEMICOLON