Difference between revisions of "PHP OO problem"

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(Created page with "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....")
 
(the question)
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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.
 
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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So the question is: is there a way to define a ''Bar::X'' method that can call ''Foo:X'' while maintaining the context of ''Bar'' (i.e. the value of ''self'' is "Bar" during execution of ''Foo::X''?

Revision as of 23:39, 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>


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.

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