Description:
------------
---
From manual page: http://www.php.net/function.array-udiff#refsect1-
function.array-
udiff-examples
---

This is my case for replacing this example code:

It uses a class when there is no need to, and then to make matters worse the 
class is 
named "cr" with no explanation as to what this means. All-lower-case class names 
go 
against prevailing PHP code standards too.

The class only has one single attribute, and it's poorly-named. A name like 
"priv_member" tells us nothing that the bare syntax doesn't already tell us.

The class' constructor is in the old "repeat the class name" style, and accepts 
another 
badly-named parameter: $val. Again, every variable is a "value" so this tells us 
nothing about what's going on.

The static comparator method is called "comp_func_cr". Presumably this means 
"Compute 
function CR". Again, we know it's a function from the syntax, we know it'll 
compute 
something because that's what functions *do*, and we know it's in the "cr" class 
because we're looking at it right now in the "cr" class.

Inside the comparator, usage of whitespace is so randomly varied as to be 
confusing to 
the reader, and thanks to all the long "priv_member" attributes it's difficult 
to see 
what's actually being compared and returned.

The instantiation code that creates arrays of "cr" objects is arranged into 
over-long 
lines, and although it defines keys for the array elements, it is not arranged 
into a 
sensible visual order from 0 to 2.

A proposed replacement is enclosed as the "test script". Its output is enclosed 
as the "actual result". The code executes the same and produces the same output 
as the existing example, but without any of the issues mentioned above.

Test script:
---------------
<?php                                                                                                                    
                                                                                                                         
$one = array(                                                                                                                                          
        '0'   => 23,                                                                                                     
        '0.1' => 9,                                                                                                      
        '0.5' => 12,                                                                                                     
        '1'   => 4,                                                                                                      
        '2'   => -15,                                                                                                    
);                                                                                                                       
                                                                                                                         
$two = array(                                                                                                            
        '0'   => 3,                                                                                                      
        '0.2' => 9,                                                                                                      
        '0.5' => 22,                                                                                                     
        '1'   => 4,                                                                                                      
        '2'   => -15,                                                                                                    
);                                                                                                                       
                                                                                                                         
$result = array_udiff($one, $two, function($a, $b) {                                                                     
        if ($a === $b) {                                                                                                 
                return 0;                                                                                                
        } elseif ($a > $b) {                                                                                             
                return 1;                                                                                                
        } else {                                                                                                         
                return -1;                                                                                               
        }                                                                                                                
});                                                                                                                      
                                                                                                                         
print_r($result);

Actual result:
--------------
Array
(
    [0] => 23
    [0.5] => 12
)