func_get_arg

This functions seems so powerful... just when i saw it i thought about writing a fast average of n numbers function so here it is, it is very simple... example usage included.<?php//Calculate the average of the numbers givenfunction avg(){    $sum = 0;    for($i = 0; $i < func_num_args(); $i++){        $sum += func_get_arg($i);    }    $avg = $sum / func_num_args();    return $avg;}echo sprintf("%.2f",avg(2,1,2,1,3,4,5,1,3,6));?>

This function may work differently from php5 to php7, in the latter it seems to reference the variable, while in php5 it returns the original argument.I have confirmed with the versions below, but this will require further confirmation as to whether this is a 5 versus 7 issue.function test( $test ){    $test = '123';    echo func_get_arg(0);}test( '321' );//in php 5.5.9, this script will write '321'//in php 7.0.33, this script will write '123'

func_get_arg() returns a *copy* of the argument, to my knowledge there is no way to retrieve references to a variable number of arguments.I have a module system in my game at http://lotgd.net where I'd like to be able to pass a variable number of arguments to functions in a module, and pass them by reference if the module asks for it by reference, but you can't accept optional parameters as references, nor can you retrieve the reference on a variable number of arguments.  Looks like my modules will have to do with out the ability to accept parameters to their functions by reference.

func_get_arg() does not appear to be allowed to be used as a function argument itself within class constructors in PHP 5.0.2 (wonk-ay!!!):<?phpclass ABC{    function __construct()    {        foreach (func_get_args() as $name => $value)        {    echo <<<EOT    <br/>    $name : $value <br/>    <br/>EOT;        }    }}class DEF extends ABC{    function __construct()    {        parent::__construct(func_get_arg(0),                                    func_get_arg(1),                                    func_get_arg(2));    }}$def = new DEF(123123, "asdfasdf", "blahblahblah");?>The above script generates:Fatal error: func_get_arg(): Can't be used as a function parameter in c:\Inetpub\wwwroot\phpwasrc\chapter10\xxx.php on line 23There are, however, no problems when passing these as parameters to regular functions.

I actually think that there is need for such "do absolutely everything" functions. I use them mostly as tools for rapid prototyping.And there is a method with which you may be able to pass several strings to a function: ereg();Another use for such functions is to create little code snippets for other people out there. They won't have to edit the function any longer if they do not use a parameter. They just don't name it when calling the function.This results in allrounder functions that are very robust in their use.Normally you just have a little code snippet (e.g. ip-blocking snippets). Through this type of programming you have whole functions.