Van Wijngaarden grammar

In computer science, a Van Wijngaarden grammar (also vW-grammar or W-grammar) is a two-level grammar which provides a technique to define potentially infinite context-free grammars in a finite number of rules.

Description

The formalism was invented by Adriaan van Wijngaarden to define rigorously some syntactic restrictions which previously had to be formulated in natural language, despite their essentially syntactical content.

Applications

Typical applications include:

• The treatment of gender and number in natural language syntax
• The well-definedness of identifiers in programming languages

The technique was used and developed in the definition of the programming language ALGOL 68.

It is an example of the larger class of affix grammars.

See also

• Affix grammar
• Attribute grammar
• Backus–Naur Form
• Computer science
• Context-free grammar
• Formal grammar
• Intermediate language

External links

• Van Wijngaarden grammar @ Wikipedia