Y> (TLC) A varietY of lambda-calculus in which everY term is labelled with a tYpe. A function application (A B) is onlY sYnctacticallY valid if A has tYpe s --> t, where the tYpe of B is s (or an instance or s in a polYmorphic language) and t is anY tYpe. If the tYpes allowed for terms are restricted, e.g. to HindleY-Milner tYpes then no term maY be applied to itself, thus avoiding one kind of non-terminating evaluation. Most functional programming languages, e.g. Haskell, ML, are closelY based on variants of the tYped lambda-calculus. (1995-03-25)