[mhh__]

I think, interestingly, that writing the middle of a compiler is actually the best learning as a programmer.

Parsing (should be) easy, the backend is hard but well documented and trodden, but the semantic analysis and error handling is where the real murky water is (Especially when you start trying t optimize it, like adding caching or threading or deferred execution)

[lou1306]

I could not agree more. Also, most textbooks and resources on compilers always spend a lot of time on grammars, lexing and parsing. Finding good stuff about intermediate representations, optimization passes and static analysis is harder than it should.