bug#54479: 27.2; Doc string of `read-char-from-minibuffer-insert-other'

[Drew Adams]

The doc string of this command is less than comprehensible, IMO.

  Handle inserting of a character other than allowed.
  Display an error on trying to insert a disallowed character.
  Also discard all previous input in the minibuffer.

To me, this doesn't say anything about what this command does.  After
all, it's a _command_, not just a function that reads a char
(presumably).  What does it do - what do you use it for?

What does "handle" mean here?  What are the "allowed" chars, and in what
way are they "allowed"?  What's meant by "previous input" here?
___

A guess is that by discarding "previous input" is meant first clear the
minibuffer - remove its content.  ("Previous input" suggests minibuffer
history.)

In GNU Emacs 27.2 (build 1, x86_64-w64-mingw32)
 of 2021-03-26 built on CIRROCUMULUS
Repository revision: deef5efafb70f4b171265b896505b92b6eef24e6
Repository branch: HEAD
Windowing system distributor 'Microsoft Corp.', version 10.0.19043
System Description: Microsoft Windows 10 Pro (v10.0.2009.19043.1526)