Polymorphic Syntax Definition (Extended Abstract)
Eelco Visser · 1995
) Eelco Visser Programming Research Group, University of Amsterdam, Kruislaan 403, NL-1098 SJ Amsterdam, The Netherlands email: [email protected], http://adam.fwi.uva.nl/visser/ Abstract Context-free grammars can be used in algebraic specification instead of first-order signatures to define the structure of algebras. The rigidity of these first-order structures enforces a choice between strongly typed structures with little genericity or generic operations over untyped structures. Two-level signatures provide a better balance between genericity and typing. Twolevel grammars are the grammatical counterpart of two-level signatures. The paper discusses generic polymorphic syntax definition in contextfree grammars and two-level grammars and investigates the problems for the practical usage of two-level grammars as signatures in algebraic specification formalisms. 1 Introduction Languages are algebras. A sentence, program or expression in a language is an object of its algebra. The ...