I'm trying to write a parser in Java for a simple language similar to Latex, i.e. it contains lots of unstructured text with a couple of \commands[with]{some}{parameters} in between. Escape sequences like \\ also have to be taken into account.
I've tried to generate a parser for that with JavaCC, but it looks as if compiler-compilers like JavaCC were only suitable for highly structured code (typical for general-purpose programming languages), not for messy Latex-like markup. So far, it seems I have to go low level and write my own finite state machine.
So my question is, what's the easiest way to parse input that is mostly unstructured, with only a few Latex-like commands in between?
EDIT: Going low level with a finite state machine is difficult because the Latex commands can be nested, e.g. \cmd1{\cmd2{\cmd3{...}}}
You can define a grammar to accept the Latex input, using just characters as tokens in the worst cast. JavaCC should be just fine for this purpose.
The good thing about a grammar and a parser generator is that it can parse things that FSAs have trouble with, especially nested structures.
A first cut at your grammar could be (I'm not sure this is valid JavaCC, but it is reasonable EBNF):