daft.functions.left#

def left(expr: Expression, nchars: int | Expression) -> Expression:
    """Gets the n (from nchars) left-most characters of each string.

    Returns:
        Expression: a String expression which is the `n` left-most characters of `self`

    Examples:
        >>> import daft
        >>> from daft.functions import left
        >>> df = daft.from_pydict({"x": ["daft", "query", "engine"]})
        >>> df = df.select(left(df["x"], 4))
        >>> df.show()
        ╭────────╮
        │ x      │
        │ ---    │
        │ String │
        ╞════════╡
        │ daft   │
        ├╌╌╌╌╌╌╌╌┤
        │ quer   │
        ├╌╌╌╌╌╌╌╌┤
        │ engi   │
        ╰────────╯
        <BLANKLINE>
        (Showing first 3 of 3 rows)

    """
    return Expression._call_builtin_scalar_fn("left", expr, nchars)