Powershell cmdlets with dynamic param AND $args don't work

Over the weekend I tried to implement auto completion in Elixir’s mix (in Windows). Unfortunately I didn’t make it without introducing some problems. So I didn’t committed my changes to upstream. Currently I try to reach some of the more renowned Elixir/Windows contributors, to discuss the changes . Motivation Under normal circumstances I don’t use more mix tasks then test, phoenix.server and release but sometimes you need this weird command, you just can’t remember.