magnars/dash.el — pull request #8 by tkf (2012-12-05 20:39:45+00:00)
Title: Add -group-by

See example:
https://github.com/tkf/dash.el/tree/group-by#-group-by-fn-list

An easy extension will be to add TEST option to make it possible to specify how keys are compared. Currently it's `equal` always.