Lambda the Ultimate

I don't know if this post strays too far from programming language theory for this forum, so please let me know if I'm criminally Off Topic. That said, I'm writing a parser library for C++ which uses a limited form of backtracking that resembles functional stream parsing. I find this parse strategy to be elegant and powerful, but it makes locating source of parse errors seemingly impossible. Does anyone know how to generate specific/useful error information in a functional stream parser?

"... we describe and compare two modern, dynamically typed languages Converge and Metalua, which both have macro-like systems. We show how, in different ways, they build upon traditional macro systems to explore new ways of constructing programs."

Contrasting compile-time meta-programming in Metalua and Converge