On Sat, May 18, 2024 at 5:18 PM Rowan Tommins [IMSoP]
<imsop....@rwec.co.uk> wrote:
>
> On 18/05/2024 15:00, Robert Landers wrote:
>
> I've been thinking about having an "internal" attribute that will emit
> a warning if called from outside it's left-most namespace.
>
>
> I like the general idea, but I don't think limiting to "left-most namespace"
> is the best semantics.
>
> It's very common for the top-level namespace to represent a vendor, and the
> *second* level to be the specific package, e.g. Doctrine\DBAL vs
> Doctrine\ORM. You've even used that in your example - I presume you've made a
> typo, and meant both examples to be calling PackageA not PackageB. In other
> cases, there are more levels - e.g. Composer package "doctrine/mongodb-odm"
> has root namespace "Doctrine\ODM\MongoDB".
I thought about that too, but in-general, a vendor has the knowledge
and capability to ensure any two packages work together (like Doctrine
plugins in your example).
>
> Possibly the attribute would need some argument to specify its granularity,
> e.g. #[Internal('\MyCompany\PackageA')],
> #[Internal('\Doctrine\ODM\MongoDB')], but that would be annoying to write
> each time.
>
That could be a useful optional parameter, and might be worth considering.
> This is another case where PHP suffers from its lack of a separate concept of
> "package" or "module" to scope things to.
>
>
> My second concern is how to implement this efficiently. The check can't
> happen at compile-time, because we don't know the definition of
> SomeOtherNamespace\Foo; so the check would need to be at run-time when the
> method/function is called. But at run-time, namespaces have very little
> existence - they really are just part of the names of functions, classes, and
> constants.
>
> So when calling a marked function, we would have to look up the name of the
> calling function or the class name of the calling method, and then do a
> string comparison against the namespace constraint. Maybe that would be easy
> and fast, I don't know.
This is a concern of mine as well, but I'm mostly curious if anyone
even wants this before I worry about implementation details. Right
now, I don't see it being any slower than type-checking, though I
foresee a bit more memory usage to keep track of the caller/callee
namespace.
>
> Regards,
>
> --
> Rowan Tommins
> [IMSoP]
