I am looking for some sample grammars written in FParsec that would go beyond the samples in the project repository.
I have found this very nice grammar of GLSL, but this is the only sample I found. What I need is a grammar for a language similar to C or JavaScript.
Luca Bolognese has written a great series of Write Yourself a Scheme in 48 Hours in F# where he used FParsec for parsing. The full source code with detailed test cases are online here.
The most relevant post is 6th one where he talked about parsing a simple Lisp-like language. This language is closer to JavaScript than to C just so you know.
Current series on his blog is parsing lambda expressions in F# (using FParsec) which could be helpful for you too.