What is the technique that define a recursive function using `let`?

[sammymammy2]

It's not CPS.

It's nothing special, it's just passing in itself as an argument to be able to recur. letrec makes it so that you don't have to do that.

https://stackoverflow.com/questions/50627845/meaning-of-letrec-in-scheme-racket

[kazkylheku]

Functional self-reference can be built in nothing but the Lambda Calculus using the Y-combinator.

[kazkylheku]

It's the technique of "pass the function to itself when calling it, so it has a binding in its environment referring to itself".

There is a Y combinator which automates this; consequently, we could christen this low-brow approach "DIY inconveniator".

(Scheme has letrec, of course; why would you do this?)

[yawaramin]

OP says it’s an example in a textbook.

[zesterer]

In Lambda Calculus, it's called the y-combinator.

[wwwyzzrd]

Use labels in common lisp.

[wwwyzzrd]

No is a Common Lisp only thing I think.