Predicate dispatch

From Wikipedia, the free encyclopedia
Jump to: navigation, search

In computer programming, predicate dispatch is a generalisation of multiple dispatch ("multimethods") that allows the method to call to be selected at runtime based on arbitrary decidable logical predicates and/or pattern matching attached to a method declaration.[1]

Julia has a package for it with PatternDispatch.jl but otherwise natively supports multiple dispatch.

Experimental implementations have been created for Common LISP,[2][3] and for Java (JPred[1]).

It allows open extension of previously declared methods at a fine-grained level, but multiple extensions with identical or overlapping predicates created by different developers may interfere with each other in unanticipated ways. In this respect it is similar to aspect-oriented programming.

References[edit]

  1. ^ a b Millstein, T.; Frost, C.; Ryder, J.; Warth, A. (2009). "Expressive and modular predicate dispatch for Java". ACM Transactions on Programming Languages and Systems. 31 (2): 1. doi:10.1145/1462166.1462168. 
  2. ^ "Predicate Dispatching in Common Lisp Object System" (PDF). 
  3. ^ "pcostanza/filtered-functions". GitHub. Retrieved 2016-04-07. 

External links[edit]