Macros aren't always a great solution. I think Haskell is the best example: many features, such as the lazy evaluation, the type system, and especially referent

Macros aren't always a great solution. I think Haskell is the best example: many features, such as the lazy evaluation, the type system, and especially referential transparency would be very hard to add on Lisp without making it very verbose and ugly. Here's an example: http://marijn.haverbeke.nl/monad.html http://marijn.haverbeke.nl/monad.html