One thing that's hard to find in #PLDev work is how to set up good error handling (both in terms of parse recovery as well as error messages).
It's interesting because it seems like such an important part of writing a language of any kind - if you think about the percentage times you compile your code and what percentage of *that* tends to have error messages in it, the error flow is just as important as the success flow -- but resources on it seem slim.
Anyone happen to know of any good reads in that regard?