This new post from Troels Knak-Nielsen on the SitePoint PHP blog shares a few helpful in-browser development tools that could come in handy in your day to day coding.

While debuggers exists, there isn't much of a tradition for using them in PHP. People have largely come to rely on injecting debugging code directly into the program, for inspecting program scope.

Tools mentioned include traceers and error handlers (like XDebug), some debugging parts of the popular PHP frameworks and the set of *cachegrind tools to help you parse the output of XDebug for profiling your application.

CodeIgniter fans might want to take note of this tip from Tiffany Brown concerning "disallowed key character" error messages.

After 6 hours of massive anxiety, stress, near tears, one pound on my desk, and some hair pulling, I tracked down the source of a nagging Disallowed Key Character error that I received while using CodeIgniter: an extra line break.

She eventually figured out that the newline and carriage return characters are not allowed as a part of the framework. Unfortunately, it was a random newline after a controller's code that did it for her.

On the Developer Tutorials blog today, Hasin Hayder has pointed out a handy PHP function that can make your debugging a bit less of a headache - debug_backtrace.

Most of the PHP developers debug php code in their local machine just by trial and error using "print_r","var_dump" and "echo". They don't write unit tests or follow any advanced debugger like xdebug. But the problem of using these methods is you cannot fool proof your code and their might be some bugs still present in your code.

He includes a simple example to show how it works and what kind of output it will give - a nested function call. Personally, I use this in some of my classes (like a database abstraction later) to track and see which functions my calls are coming from and what data they're sending me - easier to debug in one place than trying to guess.

Nick Halstead continues the "Programming Tips" series on his blog today with tip number nine (a very handy tip indeed) - using debug_backtrace from Larry Garfield.

Despite the proliferation of debugging tools, especially real-time debuggers, "debugging by print statement" remains the most common form of debugging in most programming languages.

An example of its use is included by way of a debug() function that returns the message it a bit friendlier format.

Debugging can be one of the most important tools to a developer (web or otherwise) and one of the more popular PHP IDEs, Zend Studio, makes it relatively simple to do. The Developer Tutorials website has this new tutorial to help you get started on the path to being bug free.

For the majority of experienced PHP developers, Zend Studio is considered the top-of-the-line PHP IDE. [...] In this tutorial, we will explore how to use the latest update of Zend Studio for debugging PHP scripts.

They walk through an overview of the IDE, some of the requirements and the install process and, finally, they finish it off with a few pages talking about how the get the debugging up and running.

Pierre-Alain Joye has posted an example of one way to use the XDebug software - to debug the symfony framework or any other script (with the help of vim).

Xdebug is one of the best debugger and profiler for php (maybe the only good one in open source :). The only problem is its lack of dedicated client. The only problem is its lack of dedicated client, however there is many plugins for many IDE or editors like Eclipse PDT or weaverslave and even for my favourite editor, Vim.

He quickyl runs through the installation of XDebug in your installation and the script needed to set up the debugging in vim. All that's left is to add the "XDEBUG_SESSION_START=1" flag to the end of your script name and letting the information flow in.