note 26720 deleted from function.include by sniper

From: Date: Wed, 29 Jan 2003 04:17:11 +0000
Subject: note 26720 deleted from function.include by sniper
References: 1  Groups: php.notes 
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I'm trying to design an elegant include dependency structure for a large project. My idea was using return() in libraries if some dependency wasn't loaded, and have an include manager parse the result and first include the dependency and then *retry* loading the original file after including the dependencies. To my unpleasant surprise, class definitions below the return() statement were loaded by PHP even if the return() did execute above it! The code below the return statement didn't run though, but since the class definition was loaded, retrying to load the same file resulted in a PHP error saying that I'm trying to duplicate a class! For instance: --- myFile.php --- <? include("myLib.php"); if (class_exists("myclass")) { echo("It's defined!"); } ?> --- myLib.php --- <? return(1); echo("Whoaa! return() didn't do a thing!"); class myClass { function myClass() {} } ?> Executing myFile.php *will* echo "It's defined!" but won't echo "Whoaa! return() didn't do a thing!" To further complicate things, functions will exhibit the same behaviour, and extending classes of previously defined classes will also be defined. Extending classes which haven't been previously defined however will not be defined. The explanation is simple: PHP 4 allows defining functions and classes *after* the code which uses them, so PHP must first read class and function definition in every script, and only then will it execute the code. Here's a page demonstrating this behaviour with a more extended version of the files listed above (actual sources also listed): http://bogdan.lanifex.com/PHP_include_test/myFile.php

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