Quasiquoting (part 3)

In camlp4, an antiquotation is written as $ty:var$

It means "put the AST named var, of type ty, here".

For example, writing:

let ast1 = <:expr< (fun y -> y + 1) >>
let ast2 = <:expr< List.map $expr:ast1$ [1; 2; 3] >>

Is equivalent to writing:

let ast2 = <:expr< List.map (fun y -> y + 1) [1; 2; 3] >>

Or in lisp, using backquote:

(define ast1 '(lambda (y) (+ y 1)))
(define ast2 `(map ,ast1 (1 2 3)))