A Decidable Subtyping Logic for Intersection and Union Types

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Moreover, it is not possible to have depth subtyping, namely, to generalize the types of methods that appear in the type of the object, because with method override we can give type

Terms in η-long form present several advantages (see [JG95]) and every simply-typed term M can be put in η-long form with respect to a derivation of a judgement [Hue76].

In Martin-Löf’s intuitionistic type theory, Palmgren [16] and Luo [13] formalized systems with a cumulative hierarchy of predicative universes U i and an impredicative universe

Stop considering anything can be applied to anything A function and its argument have different

Stop considering anything can be applied to anything A function and its argument have different behaviors.. Demaille Simply Typed λ-Calculus 12

The (search) rule asserts that the type of the extracted method body of n is a func- tion that accept as input argument an object, which will contains the methods m, n, together

The strong normalization theorem of second order classical natural deduction [20] is based on a lemma known as the correctness result, which stipulates that each term is in