php man page for override_function

OVERRIDE_FUNCTION(3)							 1						      OVERRIDE_FUNCTION(3)

override_function - Overrides built-in functions

SYNOPSIS
       bool override_function (string  $function_name, string  $function_args, string  $function_code)

DESCRIPTION
	Overrides built-in functions by replacing them in the symbol table.

PARAMETERS
	      o $function_name
		- The function to override.

	      o $function_args
		-  The	function  arguments,  as  a  comma  separated string.  Usually you will want to pass this parameter, as well as the $func-
		tion_code parameter, as a single quote delimited string. The reason for using single quoted strings, is to  protect  the  variable
		names from parsing, otherwise, if you use double quotes there will be a need to escape the variable names, e.g. $your_var.

	      o $function_code
		- The new code for the function.

RETURN VALUES
	Returns TRUE on success or FALSE on failure.

EXAMPLES
       Example #1

	      override_function(3) example

	      <?php
	      override_function('test', '$a,$b', 'echo "DOING TEST"; return $a * $b;');
	      ?>

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