One another big part of the CoolBasic Classic Compiler is now complete. The CB classic compiler is a standard 2-pass compiler, meaning that it consists of two major sweeps over the code in its transformation from textual representation into a byte code (the binary form is then consumed by the Cool VES runtime and game engine). There’s but one purpose for the first pass; It parses all code lines and creates lists of symbols, like functions and variables. It also picks all tokens that form expressions. Expressions are used in statements such as If, While, and assignment. We chose the 2-pass approach so that, for example, functions don’t need to be declared “above” any statements that use them. The first pass is thus essentially a gathering phase, and that is now complete. The current status is illustrated in the image below:

Green: done
Yellow: in the progress

Personally speaking, writing parsers for 40 different kinds of statements was a little repetitive and mechanical work (yes, we use specialized parsers instead of a state table and stack), but the boring part is now done. I’d say we’re definitely getting somewhere here. There are already 20,431 lines of C# code in 270 files, so the compiler project alone is pretty huge.