polars selector boolean for expression

Select all boolean columns.

Signature

> polars selector boolean {flags}

Input/output types:

inputoutput
anypolars_selector

Examples

Select all boolean columns

> {
    "name": ["Alice", "Bob"],
    "active": [true, false],
    "score": [1, 2],
} |
polars into-df --as-columns |
polars select (polars selector boolean) |
polars collect
╭───┬────────╮
│ # │ active │
├───┼────────┤
│ 0 │ true   │
│ 1 │ false  │
╰───┴────────╯