Why monads have not taken the Common Lisp world by storm

Today I was trying write a parser for a reasonably complicated language. Since I do not tend to learn from other people's work or even from my own past mistakes, and tend to greatly underestimate the complexity of tasks (or overestimate my own skills) this went something like this: Try to quickly write the whole thing as a single recursive descent parser. Note the exploding amount of ugliness. Giv

[hchbaw]

“I merrily started typing (defgeneric mreturn (val))... oh hold on. There's nothing to dispatch on: In Haskell, the kind of return we need is determined by the type deduction system — use return where an IO monad is expected, and you get the IO return, etc. In CL, this does not work.”