php - Method overiding and inheritance -

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• access level class must public error in php 3 answers
• override public method in subclass in way restricts public access while still allowing access parent class? 1 answer

the code below:

class {     public function foo() {} }  class b extends {     private function foo() {} } 

gets me error :"access level b::foo() must public (as in class a)"

why can't override class foo method in class b private?

rules of access specifiers in method overriding

the rule says:

"the subclass overridden method cannot have weaker access super class method".