Difference between revisions of "PHP OO problem"

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== The problem ==
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The ''Y'' method is only ever called via the ''self::Y'' statement in the ''X'' method, so when we call ''Bar::X()'' it's actually ''Foo::Y'' that executes, because ''X'' only ever executes within the context of ''Foo'' since we haven't overridden the ''X'' method with a definition in the ''Bar'' class.
  
But the ''Y'' method is only ever called via the ''self::Y'' statement in the ''X'' method, so when we call ''Bar::X()'' it's actually ''Foo::Y'' that executes, because ''X'' only ever executes within the context of ''Foo'' since we haven't overridden the ''X'' method with a definition in the ''Bar'' class.
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== The question ==
 
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Is there a way to define a ''Bar::X'' method that calls ''Foo:X'' while maintaining the context of ''Bar'' (i.e. the value of ''self'' is "Bar" during execution of ''Foo::X''?
'''So the question is:'''
 
 
 
:is there a way to define a ''Bar::X'' method that calls ''Foo:X'' while maintaining the context of ''Bar'' (i.e. the value of ''self'' is "Bar" during execution of ''Foo::X''?
 

Revision as of 23:44, 29 July 2013

Take the following example class Foo which defines a static method called X that statically calls another of it's method's called Y using self::Y() as follows.

<php>

class Foo {

public static function X() { self::Y(); }

public static function Y() { echo( "This is Foo::Y" ); }

} </php>


Now lets say that Foo is part of a core library that we don't have commit access to and we want to make a modified version of the functionality via a sub-class of Foo called Bar which overrides the Y method as follows.

<php>

class Bar extends Foo {

public static function Y() { echo( "This is Bar::Y" ); }

} </php>

The problem

The Y method is only ever called via the self::Y statement in the X method, so when we call Bar::X() it's actually Foo::Y that executes, because X only ever executes within the context of Foo since we haven't overridden the X method with a definition in the Bar class.

The question

Is there a way to define a Bar::X method that calls Foo:X while maintaining the context of Bar (i.e. the value of self is "Bar" during execution of Foo::X?