On 02/08/2025 15:09, Rob Landers wrote:
I’m not sure what you mean? https://3v4l.org/WKILh#v8.4.10
There is clearly shadowing going on.
There's a lot of confusing code in that example, so I'm not really sure
what it's illustrating.
This example seems more to the point: https://3v4l.org/FVhXa
Regardless of whether you look up the reflection property on the parent
or the child, it points to the same slot for property 'v'
In contrast, the same reflection code for a private property finds both
values stored in the object: https://3v4l.org/S7GmM
You can see the same result with var_dump (and serialize, and
debug_zval_dump, ...): https://3v4l.org/FqecC
I think the relevant code is this, in zend_declare_typed_property:
https://heap.space/xref/php-src/Zend/zend_API.c?r=78d96e94fa8e05dd59d03aa4891fa843ebc93ef8#4661
if (access_type & ZEND_ACC_PUBLIC) {
property_info->name = zend_string_copy(name);
} else if (access_type & ZEND_ACC_PRIVATE) {
property_info->name = zend_mangle_property_name(ZSTR_VAL(ce->name),
ZSTR_LEN(ce->name), ZSTR_VAL(name), ZSTR_LEN(name),
is_persistent_class(ce));
} else {
ZEND_ASSERT(access_type & ZEND_ACC_PROTECTED);
property_info->name = zend_mangle_property_name("*", 1,
ZSTR_VAL(name), ZSTR_LEN(name), is_persistent_class(ce));
}
For a private name, the mangled name includes the class where it's
defined, which is where the shadowing comes from: the final merged
symbol table has two differently named slots.
But for a protected name, the prefix is just "*", so it's the same slot
no matter how many times it appears in the hierarchy, just like for
public properties (whose names aren't mangled at all).
How this relates back to the original example in the thread, I'm not
sure, but it's definitely not "shadowing" in the same sense as a private
property.
--
Rowan Tommins
[IMSoP]
