fun.rkt

(require (for-syntax syntax/parse))

(define-syntax fun
  (lambda (stx)
    (syntax-parse stx
      #:literals (->)
      [(fun [v ... -> r ...] ...)
       (syntax
        (match-lambda** [(v ...) (begin r ...)] ...))])))

(check-expect
    ((fun
       [1 x -> x x]
       [_ _ -> 'fun 'fun])
     1 2)
    2)

(define-syntax just-fun
  (syntax-rules ()
    [(just-fun argument-list . body)
     ((fun . body) . argument-list)]))

(check-expect
    (just-fun [1 2]
      [1 x -> x x])
    2)