Decorated Attribute Grammars: Attribute Evaluation Meets Strategic Programming

Abstract

Abstract. Attribute grammars are a powerful specification formalism for treebased computation, particularly for software language processing. Various extensions have been proposed to abstract over common patterns in attribute grammar specifications. These include various forms of copy rules to support non-local dependencies, collection attributes, and expressing dependencies that are evaluated to a fixed point. Rather than implementing extensions natively in an attribute evaluator, we propose attribute decorators that describe an abstract evaluation mechanism for attributes, making it possible to provide such extensions as part of a library of decorators. Inspired by strategic programming, decorators are specified using generic traversal operators. To demonstrate their effectiveness, we describe how to employ decorators in name, type, and flow analysis.

An Introductory Tutorial on JastAdd Attribute Grammars

“…In addition to JastAdd, there are several other current systems that support reference attributes, including Silver [WBGK10], Kiama [SKV09], and ASTER [KSV09]. While these systems use quite different syntax than JastAdd, and support a partly different set of features, this tutorial can hopefully be of value also to users of these systems: the main ideas for how to think declaratively about reference attributes, and how to solve problems using them, still apply.…”

The spoofax language workbench

“…The data model editor uses views to generate these traces and supports the full range of editor features for editing them. -Aster [31], an attribute grammar language based on strategies for description of attribute propagation patterns. -PIL [24], a Java-like, object-oriented programming language that targets multiple software platforms.…”

“…In previous work, we applied strategic programming in the field of attribute grammars, enabling high-level, declarative specifications of semantic analyses in the Aster language [31]. Based on Aster's reusable attribute propagation patterns for name, type, and flow analysis, we would like to investigate how Aster specifications can be integrated into Spoofax and used to specify IDE services.…”

Programming Errors in Traversal Programs Over Structured Data

“…SYB, in turn, inspired cross-paradigm variations, e.g., 'Scrap your boilerplate in C++' [53]. Traversal strategies à la Stratego were also amalgamated with attribute grammars [31]. Another similar form of traversal strategies are those of the rewriting-based approach of HATS [79,76,77].…”