François Laupretre wrote on 28/04/2015 12:32:
Bare class names are still recognized and priority is given to class names (if
a 'String' class is defined, every 'String' or even 'string' type hints will
always refer to it).
This part is likely to be rather tricky to implement. How do you know if
a 'String' class is defined or not?
The Engine would have to do something like this:
- check in-scope use statements for resolutions of 'String' to a
qualified name
- if in namespace scope, try class_exists(__NAMESPACE__ '\String'),
invoking autoloader if registered
- if not in namespace scope, check class_exists('String'), invoking
autoloader if registered
- if class found, hint is an object instanceOf check
- else, hint is a scalar check
All of this (apart from resolving use statements) has to run *every time
the hint is processed*, since there is no limit on when a class can
become defined. The user has no way of avoiding this penalty, even if
they never intend to declare a String class.
In contrast, reserving the hint "string" allows the *compiler* to
immediately choose a scalar check, and an instanceOf check never needs
to run an autoloader, because if the class isn't declared, there can't
possibly be an instance of it.
Regards,
--
Rowan Collins
[IMSoP]
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