Get a list with the root column name

Description

Get a list with the root column name

Usage

<Expr>$meta$root_names()

Value

A polars expression

Examples

library("polars")

e <- pl$col("foo") * pl$col("bar")
e$meta$root_names()

#> [1] "foo" "bar"

e_filter <- pl$col("foo")$filter(pl$col("bar") == 13)
e_filter$meta$root_names()

#> [1] "foo" "bar"

e_sum_over <- pl$sum("foo")$over("groups")
e_sum_over$meta$root_names()

#> [1] "foo"    "groups"

e_sum_slice <- pl$sum("foo")$slice(pl$len() - 10, pl$col("bar"))
e_sum_slice$meta$root_names()

#> [1] "foo" "bar"