Summary of the new feature/enhancement

Currently there are ways to register a scriptblock as a completer with Register-ArgumentCompleter, and on cmdlets it's possible to use the [ArgumentCompleter()] attribute to specify an IArgumentCompleter for a parameter. But there's no way to specify a completer for an ordinary command that I know of that doesn't involve executing a scriptblock.

By this I mean, you can use Register-ArgumentCompleter or you can use override TabCompletion2, but I'd really like a nicer hook for:

• General completions
• Command completions
• Native command completions, especially