Re: master 49e06183f5 1/3: Allow REQUIRE-MATCH to be a function

[Lars Ingebrigtsen]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>>> I see that the `minibuffer-completion-confirm` function completely
>>> replaces the usual handling of require-match (i.e. the attempt to fix
>>> the case and the prompting for confirmation).
>> (You probably noticed it, but in case not -- I didn't change that code,
>> I just changed the indentation.)
>
> What I meant was that the branch you added to the `cond` overrides the
> rest of the `cond` (the part you reindented).

Ah, yes, that's true.  But REQUIRE-MATCH can't both be a function and
`confirm' at the same time, and adding a new parameter for this use case
seemed a bit overboard.

(And the function can implement its own confirm-ish action if it wants
that.)

> Understanding the subtleties can be difficult, but a good general rule
> I try to follow in such cases is to provide a function that the new
> function-hook can use to get back the old behavior.
>
> IOW, arrange your code such that the user can provide a function
> `mimic-t` where the resulting behavior is identical to providing `t`
> (and same thing for the other supported values).
> AFAICT it's currently virtually impossible (at least not without inside
> knowledge of how the minibuffer.el code is written).

But is that useful?

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no