polars.Expr.meta.pop#

Expr.meta.pop() → list[Expr][source]#

Pop the latest expression and return the input(s) of the popped expression.

Returns:

list of Expr: A list of expressions which in most cases will have a unit length. This is not the case when an expression has multiple inputs. For instance in a fold expression.

Examples

>>> e = pl.col("foo").alias("bar")
>>> first = e.meta.pop()[0]
>>> first.meta == pl.col("foo")
True
>>> first.meta == pl.col("bar")
False