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Patterns as objects in grace
Proceedings of the 8th symposium on Dynamic languages (2013)
  • Andrew P. Black, Portland State University

Object orientation and pattern matching are often seen as conflicting approaches to program design. Object-oriented programs place type-dependent behavior inside objects and invoke it via dynamic dispatch, while pattern-matching programs place type-dependent behavior outside data structures and invoke it via multiway conditionals (case statements). Grace is a new, dynamic, object-oriented language designed to support teaching: to this end, Grace needs to support both styles. We explain how this conflict can be resolved gracefully: by modelling patterns and cases as partial functions, reifying those functions as objects, and then building up complex patterns from simpler ones using pattern combinators. We describe the implementation of this design as an object-oriented framework, and a case study of its effectiveness.

Publication Date
February, 2013
Copyright (2013) Association for Computing Machinery
Citation Information
Andrew P. Black. "Patterns as objects in grace" Proceedings of the 8th symposium on Dynamic languages (2013)
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