10 Gerüchte um PHP

08 Jan, 2008

Jaybill McCarthy schreibt in seinem Blog über 10 Gerüchte um PHP und erklärt warum diese nicht zutreffen.

Gerücht #1: PHP ist nicht wirklich eine Objekt orientierte Sprache.

I hear this one a lot from Java programmers. It’s completely false. PHP has excellent OO language facilities. There’s inheritance, abstract objects, interfaces, properties and methods. Okay, there’s no method overrides, but there are ways around this. Late binding is still a bit immature. I will say that there have been vast improvements in PHP’s OO mechanics with PHP 5, but I’ve written lots of PHP 4 apps that were totally OO. The mere fact that you can write purely procedural PHP code doesn’t mean that PHP isn’t OO capable. Furthermore, the fact that PHP allows you to mix OO and procedural code makes things like bootstrap scripts really simple.

…und hoffentlich wird die OO weiterhin verbessert die wir dann in PHP6 verwenden werden. Zu diesen Verbesserungen zählen sicher namespaces an denen konkret gearbeitet wird, wie auch die Unicode-Unterstützung.

Gerücht #2: PHP fördert schlecht geschriebenen Code.

Also false. Is there a lot of sloppy PHP code around? Absolutely. PHP’s low entry barrier means that a lot of people who aren’t formally trained developers get in over their heads. The sloppy code that results is a result of poor training and bad management, not the language itself. Saying PHP encourages sloppy code is like saying hammers encourage bloody thumbs. Sure, you can bang your thumb with hammer, but is that the hammer’s fault or yours for not knowing how to use it correctly?

Das ist leider tatsächlich ein Punkt wo viele “Entwickler” den Ruf von PHP geschädigt haben und zu diesem Gerücht beigetragen haben. Natürlich ist die Sprache gewachsen und hat einige Altlasten aus PHP3 Zeiten mitgenommen(/mitnehmen müssen) um nicht mit der Kompatibiliät zu brechen. Fakt ist aber das es mit PHP absolut möglich ist guten und sauberen Code zu schreiben. Wenn man sich auch etwas mit der Sprache an sich ein wenig beschäftigt.

Gerücht #3: PHP folgt nicht dem MVC Pattern.

I know this sounds ridiculous, but I can’t tell you how many Rail-tards I’ve had this discussion with. No, PHP does not, in and of itself, provide an MVC framework. Neither does Ruby, or any language for that matter. That’s because Ruby and PHP are languages, not a application frameworks. MVC is a design pattern, not a language facility. There are many great MVC frameworks written for PHP. I like the Zend Framework. Can you make database calls from a script that also renders HTML? Sure you can. Does that mean you should? No.

Gerücht #4: PHP ist langsam weil es eine Interpretersprache ist.

This one is insidious because it sounds so plausible. In fact, it should be true. In practice, it’s not. The Zend Engine that powers most PHP implementations is ridiculously fast right out of the box. Combine it with an accelerator, (like the free eAccelerator) which pre-complies and caches the code (and re-complies it if it changes on the disk), and it’s one of the best performing application platforms around, even compared to things that are traditionally compiled, like Java and .NET. Short of writing your app in C or C++, compiling it native and hooking directly into the web server or something, you’re not really going to get much faster.

Langsam? Also ich denke das es da wieder sehr darauf ankommt, wie der Code geschrieben ist. Aber grundsätzlich stimme ich Jay völlig zu. Meine Erfahrung hat mir auch schon gezeigt das Java Web Applikation meistens sogar unter der Performance von PHP liegen. Ja ja, ich weiß….Natuerlich kommts da auch drauf an wie der Code dahinter aussieht und welche Frameworks eingesetzt werden.

Gerücht #5: PHP hat keine gute IDE und Debugger.

This is true. I doesn’t have one. It has several. There are at least two debuggers and many good IDEs . You can get all the goodies you’d expect, like breakpoints, variable watching, mouse-over evaluation, etc. Can you use a text editor and an FTP client? Sure you can. You certainly don’t have to, though.

Seit kurzem bietet Zend auch sein Zend Studio for Eclipse an. Auch beim nicht kommerziellen PDT Projekt selbst (Basis beim Zend Studio for Eclipse) hat sich einiges getan und ist, meiner Meinung nach jetzt auch wirklich einsatzbereit. Nicht zu vergessen das “alte” Zend Studio, Debugger, Profiler, etc. alles dabei.

Gerücht #6: PHP Applikationen schauen alle gleich aus.

I have to say, it took me a long time to figure out what people who made this assertion were getting at. At first I shrugged it off as if the person saying it was crazy. After all, PHP is just a language, you can make the output look like…whatever you want! Surprisingly, I’ve heard this a lot. Eventually I determined that the confusion stems from non-technical people confusing PHP with PHP-Nuke, which is just an application written in PHP. It’s fairly customizable, but deals in columns and boxes that all look kind of the same.

Gerücht #7: PHP ist nichts für “echte” und “ernsthafte” Programmierer.

This is another one I hear from Java developers (and perhaps more amusingly, .NET developers). Similar to #2, I think this stems from PHP’s low entry barrier. Pretty much anyone can learn the rudiments of hacking a PHP script together in an afternoon. Does this mean it has no place in “serious” development by “serious” developers? Well, PHP, like any development platform, is a tool. How well a tool is used varies greatly based on the skill and training of the person using it. I have written many large scale, robust, high performance applications in PHP and so have lots of other people.

Gerücht #8: PHP ist nur fürs World Wide Web

That was true once, but these days it’s pretty much general purpose. It has a command line interpreter that can be run completely independent of the web server (for scripts) but can still use your existing PHP code libraries. You can even knock together GUI applications using PHP-GTK. Admittedly, PHP’s lineage and primary purpose is web applications, but that’s far from all you can do with it.

Gerücht #9: PHP code ist nur ein Haufen voller “include” und “require” statements die schnell alles kaputt machen.

Being a scripting language, PHP is interpreted at run-time. That means any code that gets executed has to get pulled off the disk and the script in question needs to know where that is. The easiest (but by far the worst) way to do this is to place an “include” or “require” statement that loads your external script. If you do this and you move or rename a file, your script breaks unless you change the offending statement. A mess of includes and requires can make your code into spaghetti.

Fortunately, by following sound OO processes, good naming conventions and using __autoload, in-line includes and requires are generally completely unnecessary. __autoload is a callback function that accepts a class name as an argument. If you instantiate a class that the engine doesn’t know about, it calls your __autoload with the name of the class as a string. Assuming you have a reasonable naming convention, (one class per file, class name and filename match) it’s pretty trivial to load the required class when you need it. This has the side benefit of only loading classes that are actually needed for a particular script, as opposed to loading all of them before your script even runs.

Gerücht #10: In PHP Code sind häufig in-line SQL statements zu finden.

Take a look at a lot of PHP applications and you’ll see it. SQL being scraped together with concatenated strings and passed to database (often mysql) specific statements. This makes your code brittle, annoying to debug and maintain and subject to SQL-injection attacks. It’s also completely unnecessary and easily avoided. Simply use a database abstraction layer like Zend_DB or ADOdb instead of directly talking to the database.

Wie auch Jay in seinem Blog schreibt: