bug#36745: 27.0.50; completing-read with require-match nil does not accept spaces

[Jean Louis]

* Drew Adams <drew.adams@oracle.com> [2019-07-20 22:17]:
> FWIW: By default, both `?' and `SPC' are
> self-inserting for completion in Icicles
> (and have been since 2004).
> 
> But this is configurable, with option
> `icicle-completion-key-bindings'.
> 
> https://www.emacswiki.org/emacs/Icicles_-_Key_Bindings#MinibufferBinding

That is interesting. Thank you.

I have found that various completion libraries are
re-using the completing-read when necessary, so I
have to stick with completing-read for now, to
keep it minimal, and later customizable.