Quickstart

Basic usage

Version comparison examples:

>>> from versions import Version
>>> v1 = Version.parse('1')
>>> v2 = Version.parse('2')
>>> v1 == v2
False
>>> v1 != v2
True
>>> v1 > v2
False
>>> v1 < v2
True
>>> v1 >= v2
False
>>> v1 <= v2
True

Version.parse() expects a version expression string and returns a corresponding Version object:

>>> from versions import Version
>>> v = Version.parse('1.2.0-dev+foo.bar')
>>> v.major, v.minor, v.patch, v.prerelease, v.build_metadata
(1, 2, 0, 'dev', set(['foo', 'bar']))

If it isn’t a semantic version string, the parser tries to normalize it:

>>> v = Version.parse('1')
>>> v.major, v.minor, v.patch, v.prerelease, v.build_metadata
(1, 0, 0, None, None)

Version constraint matching

versions also implements version constraint parsing and evaluation:

>>> from versions import Constraint
>>> Constraint.parse('>1').match('2')
True
>>> Constraint.parse('<2').match(Version.parse('1'))
True

For conveniance, constraint matching can be tested using the in operator:

>>> '1.5' in Constraint.parse('<2')
True
>>> Version(2) in Constraint.parse('!=2')
False

Constraints can be merged using Constraints:

>>> from versions import Constraints
>>> '1.0' in Constraints.parse('>1,<2')
False
>>> '1.5' in Constraints.parse('>1,<2')
True
>>> '2.0' in Constraints.parse('>1,<2')
False