Who Modifies This Property?

Several observations in this code:

it is possible to define a property without visibility: the property hook makes it a promoted property.

It is also possible possible to create a reference on a property, as promoted properties are also an argument.

When all these features are together, it yields an error about accessing an uninitialized property.

See Also

• Uninitialized property [Try me]

PHP Error Messages

• Typed property x::$y must not be accessed before initialization

PHP Features

• promoted-property

• property-hook

• reference

• property