Why PHP sucks (for large systems)
Edwin Martin <edwin@bitstorm.org>.
Published: August 6, 2004, Last update January 2, 2006.
I have been developing in
PHP for five years now.
PHP is very easy to
program in. But
PHP also has some serious flaws.
Below I give some reasons why
PHP is not suited for anything larger
than a small hobby website.
1. Bad recursion
Recursion is the mechanism in which a function calls itself. This is a
powerful feature which can make something complex something simple.
An example of a function using recursion is
quicksort. Unfortunately,
PHP is not good at recursion. Zeev, one or the developers of
PHP, says
this:
"PHP 4.0 (Zend) uses the stack for intensive data, rather than
using the heap. That means that its tolerance recursive functions is
significantly lower than that of other languages." See bug 1901. This
is a poor excuse. Every programming language should provide good
recursion support.
2. Many PHP-modules are not thread safe
A couple of years ago, Apache released
version 2.0 of its web server.
This version supports multithreaded mode, in which one piece of software
can run multiple times simultaneously. The makers of
PHP say that the
core of
PHP is thread safe, only the non-core modules often aren't. But
nine out of ten times, you do want to use such a module in your PHP-script,
making your script unsuitable for Apache's multithreaded mode. That's
why The
PHP Group
doesn't recommend running PHP on Apache 2 in
multithreaded mode. The bad multithreaded mode support of
PHP is often
seen as the reason Apache 2 still didn't catch on.
Read the discussion about this on
Slashdot: Sites Rejecting Apache 2?.
3. PHP is crippled for commercial reasons
The performance of
PHP can be increased to 500% by using caching
[
benchmarks]. So why is caching not build into
PHP? Because Zend,
the maker of
PHP is selling its own
Zend Accelerator and of course,
they don't want to cannibalize on there own commercial products.
But there is an alternative:
APC.
4. No namespaces
Suppose someone creates a PHP-module that can read files. One of the
functions in this module is called read. And someone else's module can
read web pages and also contains a function read. Then it is impossible
to use these modules together because
PHP will not know which read
function you want.
An easy solution to this is namespaces. It was a suggested feature for
PHP 5, but unfortunately
it didn't make it. Now, without namespaces,
every function has to be prefixed with the module name, to prevent name
collisions. This leads to terrible long function names like
xsl_xsltprocessor_transform_to_xml which makes code harder to write
and read.
5. Non-standard date format characters
Many programmers are familiar with the
date format characters known
from UNIX and the C programming language. Other programming languages
adopted this standard, but strangely enough,
PHP has its own, completely incompatible date format characters. While in C, "%j" stands for the day of
the year,
in PHP this stands for the day of the month. To make things even
more confusing: the function
strftime and the
date_format of Smarty, a
PHP
templating engine, do use the C/UNIX format characters.
6. Confusing licenses
You might think
PHP is free and all
PHP-modules in the manual are free
too. Wrong. For example, if you want to generate a PDF-file from
PHP
you will find two modules in the manual:
PDF or
ClibPDF. But both come
with commercial licenses. So for every module you use, you have to make
sure you agree with its license.
7. Inconsequent function naming convention
Some function names consist of more than one word. There are three
conventions for combining these words:
Most Languages choose one of these variants.
PHP uses all of them.
For example, it you want to convert special characters to HTML entities,
you use the function
htmlentities (Words glued together). If you want to
do the opposite, you use its little brother function
html_entity_decode. For
some reason the words are now separated by underscores. Why is this
bad? You know there is a function named strpad. Or was it str_pad? Every
time you have to look up what the notation is or wait for an error to occur.
Functions are case insensitive, so for
PHP there is no difference between
rawurldecode and
RawUrlDecode. This is bad too, because both are used
and because they look different, they will confuse the reader.
8. Magic quotes hell
Magic quotes prevents PHP-scripts from SQL injection attacks. That's okay.
But for some reason, you can turn this off in the
php.ini configuration file. So
if you want to write a portable script, you always have to check whether magic
quotes is turned on or off. So a "feature" to make programming easier, actually
makes it more complex.
9. No standard framework
A website wihout a framework which grows will eventually become a
maintanance nightmare. A framework can make a lot of work easier. The
most popular model for a framework is the MVC-model, in which layout,
business logic and interaction with the database are seperated.
Many
PHP web sites don't use the
MVC-model. They don't even use a
framework. Although
some PHP frameworks do exist and you can also
write your own, articles or manuals about
PHP don't say a word about
frameworks. While JSP-developers use frameworks like
Struts and
ASP-developers use .Net, it looks like the concept of a framework is
largely unknown by
PHP developers. This says something about how
professional
PHP really is.
Update: Zend, the developer of
PHP, is working on a framework:
Zend
PHP Framework.
10. No Unicode
With Unicode it is possible to use every language in the world, for
example Chinese, Arabic and Hebrew. While every other serious
programming language supports Unicode for many years,
PHP still has
a very hard time dealing with this.
Unicode is planned for PHP 6, so we
still have to wait a long time before
PHP supports this trivial feature.
Conclusion
For very small projects, it can be a nice programming language. But for
larger and more complex projects,
PHP will show its weakness. When
you search long enough, you'll find solutions to some of the mentioned
problems. So when a solution is known, why isn't it fixed? And why are
the fixes not mentioned in the manual?
It's good that a open source language is very populair. Unfortunately, it's
not a great language. I hope all problems will be solved once (in
PHP 6?)
and we will have an open source language that's open source
and good.
Until then, when you start a project larger than five scripted pages, you'll
better consider
C#/ASP.Net or
Java/JSP as a better solution.
After I wrote this page, some people informed me about other, similar pages:
ראשי
צ'אט
13-02-2006, 20:26
מצב כלאיים
