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Re: Internals:: undocumented

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Aristotle Pagaltzis
August 15, 2016 11:02
Re: Internals:: undocumented
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* demerphq <> [2016-08-15 10:24]:
> On 14 August 2016 at 23:12, Aristotle Pagaltzis <> wrote:
> > It seems to have about a dozen actual callers on CPAN:
> >
> One of them is me in DDS. They all follow the same pattern. Someone
> read the code to Hash::Util and then unrolled what it does to lock
> keys.
> Personally I am disinclined to be sympathetic to this type of
> violation of abstraction layers.

So am I!

But what didn’t happen is me reading the entire code to DDS, spotting
that you had done this, and deciding that because you were calling
private APIs, I wouldn’t use your module. :-)

Should I have? Would you take the position that DDS breaking on me is
fair because as a user I should have examined it closely enough to
understand everything it does – including all of the guts knowledge
necessary to judge that?

Of course the abstraction violation should be cleaned up. My argument is
just about choosing an ordering of steps in such a way that people who
trusted their upstream won’t bear the punishment for (all of) upstream’s
bad choices.

Should they not trust their upstream? Part of the reason I trusted DDS,
without reading the entirety of its code, was because you wrote it, and
I knew who you are. Was I in error? Will you issue a mea culpa to all
your users for your poor judgement now? :-)

Now to be frank, I don’t truly care about assignment of blame – I ask
these questions as an argument about a general attitude, not because
I consider it a terribly productive concern on a case by case basis in
individual breakages. I’m more interested in moving forward from where
we are, whatever the reason we got there, and how to do so with minimal
collateral damage.

But one question that *would* be interesting to ponder here is… why did
*you* do that, then? :-)  Didn’t you know better?

> hv_clear_placeholders is an internals API call. Having two wrappers,
> one in Hash::Util and the other in Internals is not a big deal IMO.


Although one reason I could imagine that people used Internals:: was to
avoid having to load another module (however reasonable a call that is),
in which case being able to say “it’s going to load Hash::Util anyway”
might help persuade them to switch. I’m just guessing at this, though.

> I honestly think that people should just use the functions in
> Hash::Util directly and not use hv_clear_placeholders at all.

I don’t disagree at all. I just don’t want already-written code which
calls it to break all of a sudden.

Aristotle Pagaltzis // <>

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