pola-rs/polars · error · TypeError

cannot use glob patterns and integer based projection as `co

Error message

cannot use glob patterns and integer based projection as `columns` argument

Use columns: List[str]

What it means

Error "cannot use glob patterns and integer based projection as `columns` argument Use columns: List[str]" thrown in pola-rs/polars.

Source

Thrown at py-polars/src/polars/io/ipc/functions.py:249

    if isinstance(source, str) and is_glob_pattern(source) and is_local_file(source):
        scan = scan_ipc(
            source,
            n_rows=n_rows,
            rechunk=rechunk,
            row_index_name=row_index_name,
            row_index_offset=row_index_offset,
        )
        if columns is None:
            df = scan._collect_eager()
        elif is_str_sequence(columns, allow_str=False):
            df = scan.select(columns)._collect_eager()
        else:
            msg = (
                "cannot use glob patterns and integer based projection as `columns` argument"
                "\n\nUse columns: List[str]"
            )
            raise TypeError(msg)
        return df

    projection, columns = parse_columns_arg(columns)
    pydf = PyDataFrame.read_ipc(
        source,
        columns,
        projection,
        n_rows,
        parse_row_index_args(row_index_name, row_index_offset),
        memory_map=memory_map,
    )
    return wrap_df(pydf)


@deprecate_renamed_parameter("row_count_name", "row_index_name", version="0.20.4")
@deprecate_renamed_parameter("row_count_offset", "row_index_offset", version="0.20.4")
def read_ipc_stream(
    source: str | Path | IO[bytes] | bytes,

View on GitHub (pinned to df599052da)

When it happens

Trigger: Thrown at py-polars/src/polars/io/ipc/functions.py:249 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of pola-rs/polars@df599052da (2026-08-16). Data as JSON: /api/errors/86c7953fde66808b. Report an issue: GitHub.