# Boolean

Boolean fields store boolean values, as expected. It also provides convienence for accepting *truthy* or *falsy* values. See the usage section for more details.

### Import

`from marrow.mongo.field import Boolean`

### Inherits

`marrow.mongo:`**`Field`**

## Attributes

This field type inherits all [`Field` attributes](https://github.com/marrow/mongo/tree/128b1ec81ec6a48e05a95c32b636deede377854b/reference/field/field.md#attributes) and represents a singular, scalar boolean value. In addition to the storage and retrieval of pure `True` and `False` values, the field configuration defines allowable "truthy" values (to cast to `True`) and "falsy" values (to cast to `False`).

### `truthy`

Values to interpret as `True`, storing `True` if they are assigned.

Default`('true', 't', 'yes', 'y', 'on', '1', True)`

Added`>=1.1.3`

### `falsy`

Values to interpret as `False`, storing `False` if they are assigned.

Default`('false', 'f', 'no', 'n', 'off', '0', False)`

Added`>=1.1.3`

In versions prior to 1.1.3 the "truthy" and "falsy" values are hardcoded at the defaults presented above.

## Usage

Instantiate and assign an instance of this class during construction of a new `Document` subclass. Accessing as a class attribute will return a Queryable allowing filtering operations, and access as an instance attribute will return a `bool` cast value.

Assignment of any value matched by the `truthy` iterable (via `in` comparison) will store `True`, and likewise with the `falsy` iterable storing `False`. Additionally, if an attempt is made to assign a non-boolean, non-string value, the value will be passed through `bool()` conversion prior to storage, allowing use of objects which define their own `__nonzero__`/`__bool__` methods.