IO-Macrolanguages and Attributed Translations

By specializing the semantic-rules for attributed context-free grammars introduced by Knuth (Math. Systems Theory 2, 127–145) simple-L-attributed grammars are defined. The translations determined by these grammars are languages called value-languages. In this paper the question of classifying value-languages is considered. It is shown that the value-languages of simple-L-attributed grammars are exactly the IO-macrolanguages.