定义能够进行一次自动partial apply的函数的宏及其辅助函数

defun-partial

(defun cons-lambda-expr (fn arglist rest-args)
  (eval `(lambda ,rest-args
	   (apply ,fn (append ',arglist (list ,@rest-args))))))

(defmacro defun/partial (name arglist &body body)
  (let ((args (gensym))
	(func (gensym))
	(argc (length arglist))
	(arity (gensym))
	(rest-args (gensym)))
    `(defun ,name (&rest ,args)
       (labels ((,func ,arglist
		  ,@body))
	 (let ((,arity (length ,args)))
	   (cond ((= 0 ,arity)
		  #',func)
		 ((< ,arity ,argc)
		  (let ((,rest-args (nthcdr (- ,argc ,arity) ',arglist)))
		    (cons-lambda-expr #',func ,args ,rest-args)))
		 (t (apply #',func ,args))))))))