 DerivDecl -> [Derivation] -> EDeriv' ()
alreadyDefined derDecl = mconcat . map (checkRedef derDecl . deriv)

-- | Controla s
alreadyDefined :: DerivDecl -> [Derivation] -> EDeriv' ()
alreadyDefined derDecl = mconcat . map (checkRedef derDecl . deriv)
alreadyDefined derDecl = mconcat . map (checkRedef derDecl . deriv)