OK boys and girls, things are really starting to heat up. In this episode we start writing a compiler!

Remember, that's what we said we were going to do. We said we'd write a compiler that generates finite state machines. Well, that's what we're doing. And, boy, is it a hoot!

We begin by exploring the syntax of our state machine language. That syntax begins as a simple state transition table, and then we add a few cute bells and whistles, like super states, entry, and exit actions, that make writing state machines a bit more convenient.

Next, we formalize our syntax by expressing it in Backus-Naur Form (BNF).

Then, we write a lexical analyzer to identify the terminal tokens of our syntax.

Then, we write a parser that identifies the grammar of those terminal tokens. And, ironically, that parser is a finite state machine!

Then, we use the Builder Pattern to write a builder that constructs the internal representation of our syntax.

And if you don't think that's enough for one episode, you're crazy!

So, put your propeller caps on and take a big swig of brain juice, because we're about to plow headlong into the heady topic of Writing the State Machine Compiler!

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The source code for the State Machine Compiler is included in the "extras," and can also be found here.