Re: `isearch-allow-scroll' - a misnomer and a bad design

[Juri Linkov]

> Maybe what you want is a new option `isearch-pass-through-categories',
> which would be a list of symbol properties, so any command who has
> a non-nil value for one of those properties is allowed to run without
> exiting isearch.
>
> Then `scroll-command' becomes one possible element of
> isearch-pass-through-categories.

I think this would be the best thing to do.  And to add
a new property that doesn't exit Isearch regardless of the value of
`isearch-allow-scroll'.  And put it on all universal argument commands
`universal-argument', `negative-argument', `digit-argument', i.e.:

  ;; Universal argument commands
  (put 'universal-argument 'isearch-inhibit-exit t)
  (put 'negative-argument 'isearch-inhibit-exit t)
  (put 'digit-argument 'isearch-inhibit-exit t)

that will do TRT by default for commands unrelated to scrolling.