As far as I know, it's a pointer to the superclass. It's hard-wired with the superclass, and not dynamically figured out at runtime. Would like to know it more in de开发者_开发百科tail...
Anyone?
super
Essentially, it allows you to use the implementations of the current class' superclass.
For the gritty details of the Objective-C runtime:
[super message]
has the following meaning:
When it encounters a method call, the compiler generates a call to one of the functions objc_msgSend, objc_msgSend_stret, objc_msgSendSuper, or objc_msgSendSuper_stret. Messages sent to an object’s superclass (using the super keyword) are sent using objc_msgSendSuper; other messages are sent using objc_msgSend. Methods that have data structures as return values are sent using objc_msgSendSuper_stret and objc_msgSend_stret.
So yes, it is static, and not determined at runtime.
It's a keyword that's equivalent to self
, but starts its message dispatch searching with the superclass's method table.
super
is not a pointer to a class. Super is self
, but when used in a message expression, it means "look for an implementation starting with the superclass's method table."
These blog postings on what is a meta class?, getting subclasses and classes and metaclasses may give you some insight on the internals of this.
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