Zend: Make instanceof object equivalent to is_object()#22375
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`$x instanceof object` was syntactically valid but always returned false because `object` is a pseudo-type with no corresponding class entry in the class table. This made the construct silently unusable. At compile time, when the right-hand side of `instanceof` is the literal `object` pseudo-type, emit `ZEND_TYPE_CHECK` with `MAY_BE_OBJECT` instead of `ZEND_INSTANCEOF`. This is the same opcode used by `is_object()`, so `$x instanceof object` now behaves identically to `is_object($x)`. The fix is entirely at compile time; no VM handler changes are required.
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This reinforces an inconsistency in how pseudotypes are allowed to be used in different contexts. That should be resolved first.
In type declarations, object must be unqualified or you get a fatal error.
But this is still allowed in your PR: var_dump((new stdClass) instanceof \object);.
Also not a fan of allowing pseudotypes, one could make an argument that 3 instanceof int should also be supported; if instanceof object is supported.
Girgias
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Girgias
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I agree with Nora, only supporting object introduces a new inconsistency. Something that would be resolved with @iluuu1994's pattern matching RFC introducing the new is keyword where you can check for types in a more generic way than instanceof.
Marking as requesting change as I do think this is contentious and would better be suited by a small RFC for people to properly establish semantics.
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Fine with me. Let's close this and not make anyone else loose time on this. |
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$x instanceof objectwas syntactically valid but always returned false becauseobjectis a pseudo-type with no corresponding class entry in the class table. This made the construct silently unusable.At compile time, when the right-hand side of
instanceofis the literalobjectpseudo-type, emitZEND_TYPE_CHECKwithMAY_BE_OBJECTinstead ofZEND_INSTANCEOF. This is the same opcode used byis_object(), so$x instanceof objectnow behaves identically tois_object($x).The fix is entirely at compile time; no VM handler changes are required.