[Haskell-cafe] Parsec: buildExpressionParser of a different type than parsed term

Folks, I'm trying to parse NumExpr > NumExpr (example) which should return a logical expression while parsing numeric terms. I can't figure out how to make buildExpressionParser do this for me since it takes the type of the term parser given to it. If I supply a parser for numeric terms then I cannot return a logical expression. How can this be resolved? Note that I do not want to put all expressions into the same Expr type since it makes generating valid random ASTs with QuickCheck impossible. Thanks, Joel -- http://wagerlabs.com/