-- | Finds free variables in an expression selected by a predicate
exprSomeFreeVars :: InterestingVarFun   -- ^ Says which 'Var's are interesting
                 -> CoreExpr
                 -> VarSet
exprSomeFreeVars fv_cand e = fvVarSet $ filterFV fv_cand $ expr_fvs e
exprSomeFreeVars :: InterestingVarFun   -- ^ Says which 'Var's are interesting
                 -> CoreExpr
                 -> VarSet
exprSomeFreeVars fv_cand e = fvVarSet $ filterFV fv_cand $ expr_fvs e
exprSomeFreeVars fv_cand e = fvVarSet $ filterFV fv_cand $ expr_fvs e