The Community for Technology Leaders
Green Image
<p>We propose a family of static evaluators for subclasses of the well-defined (i.e., noncircular) attribute grammars. These evaluators augment the evaluator for the absolutely noncircular attribute grammars with look-ahead behaviors. Because this family covers exactly the set of all well-defined attribute grammars, well-defined attribute grammars may be classified into a hierarchy, called the $NC$ hierarchy, according to their evaluators in the family. The location of a noncircular attribute grammar in the $NC$ hierarchy is an intrinsic property of the grammar. The $NC$ hierarchy confirms a result of Riis and Skyum, which says that all well-defined attribute grammars allow a (static) pure multivisit evaluator by actually constructing such an evaluator. We also show that, for any finite $m$, an $NC(m)$ attribute grammar can be transformed to an equivalent $NC(0)$ grammar.</p>
attribute grammars, noncircular attribute grammars, ordered attribute grammars, pure multivisit attribute grammars, simple multivisit attribute grammars, well-defined attribute grammars, grammar classification

W. Yang, "A Classification of Noncircular Attribute Grammars Based on the Look-Ahead Behavior," in IEEE Transactions on Software Engineering, vol. 28, no. , pp. 210-227, 2002.
85 ms
(Ver 3.3 (11022016))