override_function
    (PECL)
override_function -- Overrides built-in functions
Description
bool 
override_function ( string function_name, string function_args, string function_code )
     Syntax similar to create_function(). Overrides built-in functions
     (replaces them in the symbol table).
    
     
Example 1. override_function() example 
<?php override_function('test', '$a,$b', 'echo "DOING TEST"; return $a * $b;'); ?>
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