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