(definition)
Definition: A language that does not allow any destructive operation---one which overwrites data---such as the assignment operation. Purely functional languages are free of side effects, i.e., invoking a function has no effect other than computing the value returned by the function.
Note: From Algorithms and Theory of Computation Handbook, page 5-24, Copyright © 1999 by CRC Press LLC. Appearing in the Dictionary of Computer Science, Engineering and Technology, Copyright © 2000 CRC Press LLC.
Author: CRC-A
If you have suggestions, corrections, or comments, please get in touch with Paul E. Black.
Entry modified 17 December 2004.
HTML page formatted Mon Sep 11 09:46:06 2006.
Cite this as:
Algorithms and Theory of Computation Handbook, CRC Press LLC, 1999, "purely functional language", in
Dictionary of Algorithms and Data
Structures [online], Paul E. Black, ed.,
U.S. National Institute of
Standards and Technology. 17 December 2004. (accessed TODAY)
Available from: http://www.nist.gov/dads/HTML/purelyfnctnl.html