Principal Typing in Elementary Affine Logic

Elementary Affine Logic (EAL) is a variant of the Linear Logic characterizing the computational power of the elementary bounded Turing machines. The EAL Type Inference problem is the problem of automatically assign to terms of λ-calculus EAL formulas as types. The problem is solved by showing that every λ-term which is typeable has a finite set of principal typing schemata, from which all and only its typings can be derived, through suitable operations. An algorithm is showed, that gives as output, for every λ-term, either a negative answer or the set of its principal typing schemata.