Coding Binding and Substitution Explicitly in Isabelle

Logical frameworks provide powerful methods of encoding object-logical binding and substitution using meta-logical λ-abstraction and application. However, there are some cases in which these methods are not general enough: in such cases object-logical binding and substitution must be explicitly coded. McKinna and Pollack [MP93] give a novel formalization of binding, where they use it principally to prove meta-theorems of Type Theory. We analyse the practical use of McKinnaPollack binding in Isabelle object-logics, and illustrate its use with a simple example logic.