Tags: Programming Language.
LR-attributed grammars are a special type of attribute grammars. They allow the attributes to be evaluated on LR parsing. As a result attribute evaluation in LR-attributed grammars can be incorporated conveniently in bottom-up parsing. zyacc is based on LR-attributed grammars. They are a subset of the L-attributed grammars where the attributes can be evaluated in one left-to-right traversal of the abstract syntax tree.