uniontypes

Union types for python


License
GPL-2.0
Install
pip install uniontypes==0.1.0

Documentation

uniontypes 0.1

build status

Union types For python.

These appear other languages like Haskell (Either) and Scala (Union or \/).

This extends to any arbirary set of types.

Examples

Creating a union type

>>> from uniontypes import Union
>>> u = Union[list, tuple, str]
>>> u
<class 'uniontypes.Union[list, tuple, str]'>

Creating boxed values

>>> u([1, 2, 3])
Union[list, tuple, str][list] [1, 2, 3]
>>> u((1, 2, 3))
Union[list, tuple, str][tuple] (1, 2, 3)
>>> u('123')
Union[list, tuple, str][str] '123'

Accessing the inner wrapper types

>>> u[list]
<class 'uniontypes.Union[list, tuple, str][list]'>
>>> u[tuple]
<class 'uniontypes.Union[list, tuple, str][tuple]'>
>>> u[str]
<class 'uniontypes.Union[list, tuple, str][str]'>

Class heirarchy

>>> isinstance(u([1, 2, 3]), u)
True
>>> isinstance(u([1, 2, 3]), u[list])
True
>>> isinstance(u([1, 2, 3]), (u[tuple], u[str]))
False

Option Types

>>> from uniontypes import Option
>>> oint = Option[int]
>>> oint
<class 'uniontypes.Option[int]'>
>>> oint(1)
Option[int] 1
>>> oint(None)
Nothing
>>> oint(None) is oint.nothing
True