Editing S-attributed grammar

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'''S-attributed grammars''' are a class of [[attribute grammar]]s characterized by having no [[Attribute_grammar#Inherited_attributes| inherited attribute]]s, but only [[Attribute_grammar#Synthesized_attributes| synthesized attribute]]s. Inherited attributes, which must be passed down from parent nodes to children nodes of the [[abstract syntax tree]] during the [[Semantic analysis (computer science)|semantic analysis]] of the [[parsing]] process, are a problem for [[bottom-up parsing]] because in bottom-up parsing, the parent nodes of the abstract syntax tree are created ''after'' creation of all of their children. Attribute evaluation in S-attributed grammars can be incorporated conveniently in both [[top-down parsing]] and [[bottom-up parsing]].

Specifications for parser generators in the [[Yacc]] family can be broadly considered S-attributed grammars. However, these parser generators usually include the capacity to reference global variables and/or fields from within any given grammar rule, meaning that this is not a ''pure'' S-attributed approach.

Any S-attributed grammar is also an [[L-attributed grammar]].

==See also==
* [[Attribute grammar]]

{{DEFAULTSORT:S-Attributed Grammar}}
[[Category:Formal languages]]
[[Category:Compiler construction]]