(input)
(output "Named fn through a pointer: 30"
        "Lambda through a pointer: 30"
        "Lambda called in place: 130"
        "Nested lambdas: 666")
(return 0)

;;; Lambdas are lifted into toplevel functions by semen, so what this
;;; really checks is that the lifted `fn' comes out in the argument
;;; order the writer expects -- (fn name arglist ret-type . body).

(include stdio.h)

(fn sum ((a int) (b int)) int
  (return (+ a b)))

(pub fn main () int
  (var a int 10)
  (var b int 20)

  (var sum-fn (fn ((int) (int)) int) sum)
  (printf "Named fn through a pointer: %d\n" (sum-fn a b))

  (var sum-lambda (fn ((int) (int)) int)
       (lambda ((a int) (b int)) int ()
         (return (+ a b))))
  (printf "Lambda through a pointer: %d\n" (sum-lambda a b))

  (printf "Lambda called in place: %d\n"
          ((lambda ((a int) (b int)) int ()
             (return (+ a b 100)))
           a b))

  ;; A lambda inside a lambda: the inner one is lifted out of a
  ;; function that is itself being lifted
  (var outer (fn ((int)) int)
       (lambda ((x int)) int ()
         (var inner (fn ((int)) int)
              (lambda ((y int)) int ()
                (return (+ 60 y))))
         (return (+ 600 (inner x)))))
  (printf "Nested lambdas: %d\n" (outer 6))

  (return 0))