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copied!<p>I noticed that there are some functions such as <code>is_int()</code> or <code>isset()</code> or <code>file_exists()</code> or <code>functions_exists()</code> that are somehow very useful. When I write some code I do always think to every bad things that could happen to my site, but sometime I face problems such as:</p> <blockquote> <p>Wait, this variable is set inside the PHP file; this means that no one could ever edit it, right? And if this "user" could edit it I would have a lot of more troubles because it would be able to manage the PHP file.</p> </blockquote> <p>or </p> <blockquote> <p>Does this really worth something to keep checking for file that should exists always?</p> </blockquote> <p>Let's consider the following example which has no sense by its own, but will help me in order to make you understand what I'm talking about. PS: I exaggerated the code on purpose.</p> <p><strong>config.php</strong></p> <pre><code>$doActions = true; </code></pre> <p><strong>functions.php</strong></p> <pre><code>function getID() { return $_COOKIE['userid']; } class eye { public static function see() { // gain the object the user is looking at return $object; } } </code></pre> <p><strong>index.php</strong></p> <pre><code>class viewer { private $poniesSeen = 0; public function __construct() { /* Magic ponies are created here */ } public function sawAPony($id) { if (file_exists('config.php')) { if (isset($doActions)) { if (is_bool($doActions)) { if ($doActions) { if (file_exists('functions.php')) { if (function_exists('getID')) { $id = getID(); if (!empty($id)) { if (!is_int($id)) { settype($id, 'int'); } if (class_exists('eye')) { if (method_exists('eye', 'see')) { $o = eye::see(); if (is_string($o)) { if ($o = 'pony') { if (isset($this->poniesSeen) and is_int($this->poniesSeen)) { ++$this->poniesSeen; return true; } else { return false; } } else { return false; } } else { return false; } } else { return false; } } else { return false; } } else { return false; } } else { return false; } } else { return false; } } else { return false; } } else { return false; } } else { return false; } } else { return false; } } } </code></pre> <p>Now, I think, which of this conditions should be kept and what thrown away because they have no sense at all? Why should I not check for them and why should I? Is there a golden-rule about this kind of obsessions?</p>

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