Rigorous pattern matching as a language feature

Structural pattern matching as a language feature has become more common in programming languages over the past decade. This paper will consider more generally the challenge of adding pattern matching as a programming language feature, from the points of view of language design, rigorous static error detection, and effectiveness. In this context, a pattern-matching language feature can be seen as providing a more rigorous approach to handling the complex conditionals that arise in processing highly structured input.