New on PHPBuilder.com today Leidago Noabeb gives you a pretty comprehensive overview of error handling in PHP - everything from the types of errors to how to control which are output in which environments.

In this article we will be looking at how to handle errors in PHP. Errors are an inevitable part of software development, and accordingly, we will be looking at the various error types and demonstrating how to handle them. If you intend to run any of the sample scripts in this article, please make sure that display errors is turned on in your PHP initialization document (php.ini).

The article talks about the types of errors PHP uses (syntactical, runtime and logical) and shows how to handle some of the most common issues with them. It also talks about the different error reporting levels (ex. E_ALL, E_WARNING, E_STRICT) and includes the code for a simple error handler class that switches off and handles each type differently.

Unit testing in PHP applications is growing more and more in popularity, so much so that some developers get into it, test all of their code and aren't exactly sure when enough is enough. Jim Plush has a suggestion for those kinds of testers - consider the cyclomatic complexity.

To illustrate, he gives a simple example of a function with only a function call and return inside. This has a cyclomatic complexity rating of 1 (the lowest). Now, start adding in ifs, loops, and other ways for the data to go and you start adding more complexity levels. Jim suggests that this can be another useful unit testing measurement - one more unit test for each level of complexity.

He also notes a pleasant side effect of this sort of classification: