15-851 Computation and Deduction
Lecture 18: Unification
The description of the unification logic in the logical framework is
immediately executable as an algorithm for unification. This is because
unification is directly available as part of the operational semantics of Elf.
In this lecture we describe more a more explicit algorithm for unification.
We also talk in detail about the way that the correctness proof for
constraint-based type inference is implemented in Elf. This shows a number of
new techniques in dealing with parametric and hypothetical judgments.