gistfile1.php

<?php
function _define($name,$default_value,$development_value=NULL){
	$name = (string) $name;
	if(defined($name)){
		trigger_error('Previously Defined Constant: '.$name, E_USER_WARNING);
		return FALSE;
	}
	else{
		if((ENVIROMENT == 'PRODUCTION') || (ENVIROMENT == 'DEVELOPMENT') || is_null($development_value)){
			define($name,$default_value);
		}
		else{
			define($name,$development_value);
		}
	}
}