In the theory of programming languages in computer science, deforestation (also known as fusion) is a program transformation to eliminate intermediate lists or tree structures that are created and then immediately consumed by a program.
The term "deforestation" was created by Philip Wadler, originally in his 1990 paper "Deforestation: transforming programs to eliminate trees".1
Deforestation is typically applied to programs in functional programming languages, more so non-strict programming languages such as Haskell. One algorithm for deforestation, named shortcut deforestation,2 is implemented in the Glasgow Haskell Compiler.3 Deforestation is closely related to escape analysis.
References
References
- Wadler, Philip (1990). "Deforestation: transforming programs to eliminate trees". Theoretical Computer Science. 73 (2): 231–248. doi:10.1016/0304-3975(90)90147-A.
- Gill, Andrew; Launchbury, John; Peyton Jones, Simon (1993). "A short cut to deforestation" (PDF). Proceedings Conference on Functional Programming Languages and Computer Architecture. pp. 223–232. doi:10.1145/165180.165214.
- Peyton Jones, Simon; Tolmach, Andrew; Hoare, C.A.R. (2001). "Playing by the rules: rewriting as a practical optimization technique in GHC" (PDF). Proceedings ACM/SIGPLAN Haskell Workshop.