addTickHsExpr (HsLet binds e) =
        bindLocals (collectLocalBinders binds) $
        liftM2 HsLet
                (addTickHsLocalBinds binds) -- to think about: !patterns.
                (addTickLHsExprLetBody e)
addTickHsExpr (HsLet binds e) =
        bindLocals (collectLocalBinders binds) $
        liftM2 HsLet
                (addTickHsLocalBinds binds) -- to think about: !patterns.
                (addTickLHsExprLetBody e)
addTickHsExpr (HsLet binds e) =
        bindLocals (collectLocalBinders binds) $
        liftM2 HsLet
                (addTickHsLocalBinds binds) -- to think about: !patterns.
                (addTickLHsExprLetBody e)