#lang scheme

(require (for-template scheme/base scheme/contract))

(provide checking-proc)

(define-syntax (checking-proc stx)
  (syntax-case stx ()

    [(_ internal-name (x ...))
     #'(lambda (syn)
         (syntax-case syn ()
           [(_ x ...)
            (quasisyntax/loc syn
              (internal-name x ...))]
           [(_ y (... ...))
            (raise-syntax-error #f 
              (format "Expected ~a arguments, but got ~a"
                      (length '(x ...))
                      (length (syntax->list #'(y (... ...)))))
              syn)]
           [_ (raise-syntax-error #f
                "Functions may be used only in operator position." syn)]))]))