Examples
Here are examples of Common Lisp code.
The basic "Hello world" program:
(print "Hello world")Lisp syntax lends itself naturally to recursion. Mathematical problems such as the enumeration of recursively defined sets are simple to express in this notation.
Evaluate a number's factorial:
(defun factorial (n) (if (<= n 1) 1 (* n (factorial (- n 1)))))An alternative implementation, often faster than the previous version if the Lisp system has tail recursion optimization:
(defun factorial (n &optional (acc 1)) (if (<= n 1) acc (factorial (- n 1) (* acc n))))Contrast with an iterative version which uses Common Lisp's loop macro:
(defun factorial (n) (loop for i from 1 to n for fac = 1 then (* fac i) finally (return fac)))The following function reverses a list. (Lisp's built-in reverse function does the same thing.)
(defun -reverse (list) (let ((return-value ')) (dolist (e list) (push e return-value)) return-value))Read more about this topic: Lisp (programming Language)
Famous quotes containing the word examples:
“No rules exist, and examples are simply life-savers answering the appeals of rules making vain attempts to exist.”
—André Breton (1896–1966)
“It is hardly to be believed how spiritual reflections when mixed with a little physics can hold people’s attention and give them a livelier idea of God than do the often ill-applied examples of his wrath.”
—G.C. (Georg Christoph)
“In the examples that I here bring in of what I have [read], heard, done or said, I have refrained from daring to alter even the smallest and most indifferent circumstances. My conscience falsifies not an iota; for my knowledge I cannot answer.”
—Michel de Montaigne (1533–1592)