composer/composer — pull request #968 by jmalloc (2012-08-02 06:19:44+00:00)
Title: Support for "~" version constraint operator for projects that use Semantic Versioning.

This PR provides support for a new version constraint operator specified with the tilde character.
It behaves similarly to the operator of the same name in [npm](https://npmjs.org/doc/json.html#Tilde-Version-Ranges).

For example, specifying the version constraint as `~1.2.0` is functionally equivalent to `>=1.2.0,<2.0.0`. If the package adheres to the [semantic versioning](http://semver.org) specification then any version in this range is guaranteed to be compatible.