RE: [External] : Re: Smarter M-x that filters on major-mode

[Drew Adams]

> Another idea that I once had is that to make a special M-x such that it
> only contains some selected commands, and as soon as there is only one
> candidate left, it is immediately executed (without pressing RET). This
> is somewhat between a keybinding and normal M-x.

It's trivial to define a command like `M-x' that
limits the available command names using a predicate.
___

Option `icicle-top-level-when-sole-completion-flag'
does what you suggest for a sole matching candidate:

 Non-nil means to return to top level if only one
 matching completion. The sole completion is accepted.

Option `icicle-top-level-when-sole-completion-delay'
is the number of seconds to wait before doing that.
Editing the completion (typing or deleting a char)
before the delay expires prevents its automatic
acceptance.