LinPad is a lightweight programmer’s text editor I developed between eighth and ninth grade. It started out as a Notepad clone for Linux, but I ended up adding features like syntax highlighting, code completion and more. It includes a simple XML format to describe the regular expressions needed to highlight different values in the code. I have provided highlighting schemes for C/C++, Java and HTML.
It doesn’t include project management, it isn’t particularly fast, and it certainly won’t cook your meals for you, but it was an excellent way for me to get started learning GUI development and code analysis.