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The long-term strategy behind incredible recruiting

From the very start of my thesis, the key idea was to find a lambda calculus with explicit substitutions, indexes, and all the good properties (I refer the reader to all previous posts). In particular, having in mind a recent work from Delia Kesner

In all previous posts I’ve tried to teach the different aspects inside my thesis. But after going deeper and deeper, the concepts tend to complicate too much, and much more dedication from the reader is needed. After trying to add another technical...

In this post I will show two different sets of properties that any variation of λ-calculus with explicit substitutions may or must have. The must: Any substitution must end, i. e. the process of change a variable by a term must always end, no matter...

As I told you before, performance is something desirable when programming a λ interpreter. The sustitutions we saw are made in one step. I will note the beta step as →β and a substitution step as →. For instance, (λx.x) z  →β  x[x/z]  →  z. The computations...

With this cite of Monthy Python, I will move into another family of calculi. What’s wrong with our good ol’ λ-calculus? Nearly nothing, except if you want to implement it in a real PC. In one of the firsts posts I’ve mentioned the α-congruence. The...

As you probably already know, recursive function are those that call them self. For instance, you can define the factorial function as: fact(0) = 1 fact(n) = n*fact(n-1) This doesn’t look like something you can say with the small syntaxis of the ...

One simple way to make arithmetic expressions in lambda calculus, is just to extend the calculus with the arithmetic rules: (λx.(λy. x+y)) 2 3 → (λy. 2+y) 3 → 2+3 = 5 But that’s pretty easy for us, and (as you problably have already noticed) we like...

From the Wikipedia: “calculus can refer to any method or system of calculation”, and that’s not an exception for the Lambda Calculus. First of all, lets define the terms of this calculus: A Lambda Term is something with the form x where x is in...

A Term Rewriting System (TRS) is a very powerful yet simple math tool used, for instance, for the creation of computational models. Given a set of function symbols S, and an (uncountable) set of variables V, I will define rewriting rule by example...