RE: [External] : Questions about transient (was: Re: A different way to interactively pass options to commands)

[Drew Adams]

> If transient is included in Emacs core, that would be a good reason for
> me to consider moving one of my packages

This.  A 3rd-party library is (much) more likely to make use of something 
that's part of Emacs than it is to provide code that hard-code depends on an 
external library.