コンストラクタを簡単に書く ref: http://qiita.com/Hiraku/items/84156e0ed0dc0937e44c

file0.php

<?php
//こんな風に書けるとドリーム感いっぱい！？
class Point
{
      private $x, $y;      
      public function __construct($this->x, $this->y);
} 

file2.php

<?php
class Foo
{
    private $a, $b, $c, $d;
    function __construct($a, $b, $c, $d)
    {
        foreach (get_defined_vars() as $key => $val) $this->$key = $val;
    }
}

file3.php

<?php
class Foo
{
    private $_a, $_b, $_c, $_d;
    function __construct($a, $b, $c, $d)
    {
        foreach (get_defined_vars() as $key => $val) $this->{"_$key"} = $val;
    }
}

こういう代入コードは不毛ですよね

<?php
class Foo
{
    private $a,$b,$c,$d;
    function __construct($a, $b, $c, $d)
    {
        $this->a = $a;
        $this->b = $b;
        $this->c = $c;
        $this->d = $d;
    }
}