Re: PATCH: "unset -n" removes nameref-ness

[Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>]

On Tue, Jun 10, 2025 at 8:38 AM Philippe Altherr
<philippe.altherr@xxxxxxxxx> wrote:
>>
>> } else /* should this be in unsetparam_pm()? */
>
> I was expecting to find code that clears flags like PM_INTEGER in either bin_unset or in unsetparam_pm but I don't see anything like that. So it's a bit of a mystery to me how and where these flags get cleared and why only PM_NAMEREF needs to be explicitly cleared in bin_unset (or unsetparam_pm).

The flags are assigned at the end of createparam(), overwriting
whatever the old flags were.  PM_NAMEREF is checked too early for
that, to cause the assignment to go through to the referent instead.
So that has to be cleared before we reach createparam().

For top-level parameters, this doesn't apply, because unsetparam_pm()
discards them entirely from the parameter table, but it can't do that
for locallevel > 0.

> For code with no errors, clearing PM_NAMEREF in bin_unset seems good enough but there are all these places that check for errors and then sometimes unset a parameter

That's likely to be a tricky one.  An implicit reversal of an
assignment rather than an explicit unset -n might not always be
expected to undo the declaration.