Abstract not found

Origin Tracking is a technique which, in the framework of first-order term rewriting systems, establishes relations between each subterm t of a normal form and a set of subterms, the origins of t, in the initial term. Origin tracking is based on the notion of residuals. It has been used successfully for the generation of error handlers and debuggers from algebraic specifications of programming languages. Recent experiments with the use of higher-order algebraic specifications for the definition of programming languages revealed a need to extend origin tracking for higher-order term rewriting systems. In this paper, we discuss how origin information can be maintained for fij reductions and expansions, during higher-order rewriting. We give a definition of higher-order origin tracking. The suitability of this definition is illustrated with a small, existing specification. AMS Subject Classification (1991): 68N20, 68Q55, 68Q65. CR Subject Classification (1991): D.2.5, D.2.6, D.3.4, F.3...

Algebraic specifications of programming languages can be used to generate language-specific programming support tools. Some of these can be obtained in a straightforward way by executing language specifications as term rewriting systems. More advanced tools can be obtained if the term rewriting machinery is extended with origin tracking . Origin tracking is a technique which automatically establishes a relation between subterms of the result value (normal form) and their origins , which are subterms of the initial term. For specifications having a syntax-directed nature, as formalized by the class of so-called primitive recursive schemes, high-quality origins can be established. The definition, properties, extensions, and implementation of these so-called syntax-directed origins are discussed.

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