There are a lot of books on domain specific languages (DSLs). Such books talk about compilers, interpreters, parsing, lexing, semantic analysis, and other various bits someone needs to implement a DSL.
I already know how to implement a DSL; I've implemented several. However, several such DSLs have been monsters to work with. One starts out with whatever features one wants to support in the DSL, only to find that more features get added later, resulting in a mess of wacky and inconsistent conventions.
I'm going to be designing a new DSL here and I want to start off on the correct foot, with an eye this time for future expansion of the language. The few books I've been able to find on language design seemed to be focused on general purpose (and C derived) language design, which is not a path that makes sense for my domain.
What kinds of references or books are available on this topic?