curry.rkt

#lang racket

(define (curry f)
  (define (min-arity arity)
    (if (number? arity) arity (arity-at-least-value arity)))
  (define (curry-aux f args arity)
    (lambda (a)
      (let ((new-args (cons a args)))
        (cond ((= arity 1)
               (apply f (reverse new-args)))
              ((> arity 1)
               (curry-aux f new-args (- arity 1)))
              ; fail otherwise
              ))))
  (curry-aux f '() (min-arity (procedure-arity f))))


(define (appc . l)
  (if (eq? (cdr l) '())
      (car l)
      (apply appc 
             (cons ((car l) (cadr l)) (cdr (cdr l))))))

example

 (appc (curry (lambda (a b) (+ a b))) 1 2)