I'm not sure when this came out, but Google now has source code search. These guys never stop amazing me.
So what you need to do now is create a new bookmark in firefox. Point it to: http://www.google.com/codesearch?hl=en&q=+lang:php+%s
Give it a name and in the keyword field, put something like 'phpcode'. Save it.
Now in your address bar, type 'phpcode array_merge' and return.
IMHO, the worst part of Drupal is having to learn the API. The core developers are constantly refactoring the heart of Drupal, which is a good thing overall. But it makes it very difficult for the average developer to keep up with the API. Major version releases prior to 4.7 required a developer to make relatively few changes to his module to make it compatible with the new release. 4.7, on the other hand, requires pretty much a complete rewrite of a given 4.6 module.
I recently worked on a project which required a updated version of the jQuery library. While there is the jQuery Update module, it only allows you to upgrade Drupal 6 to jQuery 1.3. If you really know what you're doing and want to upgrade beyond that version, you can either hack core or create your own simple module to do it. While hacking core is certainly the easier approach (simply overwriting misc/jquery.js with a newer version), it is very bad practice.
You say you want to build a website? It must be feature rich, flexible, extensible, powerful, and very web2.0. This is an important site, and you don't want to be locked in to someone else's framework, so you have decided the smartest approach is DIY. You have a small team of very experienced LAMP developers who have track record building successful sites. They've promised to meet your every requirement.
The following is a guest post by Mitchel Xavier
One of the challenges of developing with Drupal is to understand Drupal’s structure. Until now, when working with the DOM structure, the DOM inspector has been the best tool for viewing the structure. A new tool has been created to make the visualization of the DOM structure much easier to interpret. It is a Firefox add-on and is called Tilt 3D. It creates 3 dimensional interactive representation of the DOM elements as a layered visual image.