Topic: van Wijngaarden grammar

topics > communication > natural language > Group: grammar

attribute grammar
formal methods and languages
semantic grammar


van Wijngaarden grammars specified ALGOL 68's syntax. They are two-level grammars which allow language statements, e.g., declarations, to modify the grammar. This could completely define the language's syntax and semantics. van Wijngaarden grammars are difficult to understand. (cbb 5/80)
Subtopic: 1-level Wijngaarden up

QuoteRef: kostCH_1974a ;;148 1-level Wijngaarden grammars same as BNF but uses a different syntax

Subtopic: 2-level Wijngaarden up

Quote: 2-level van Wijngaarden grammars define meta rules that generate BNF rules [»kostCH_1974a, OK]
QuoteRef: kostCH_1974a ;;150 in 2 level van Wijngaarden grammar most productions will fail

Subtopic: declaration as rule up

Quote: the declarative statements of a program could define a context-free grammar for its imperative statement [»hanfKV_1973]
Quote: with van Wijngaarden grammars can specify that all variables in a declaration list have the given type
Quote: declarations define what variables can be used in a program's statement productions [»hanfKV_1973, OK]

Subtopic: execution as rule up

Quote: a van Wijngaarden grammar generates all correct executions of a program as 'program input output' [»pagaFG3_1979]

Subtopic: problems with van Wijngaarden grammar up

Quote: van Wijngaarden's approach may be too subtle and intricate to explain a programming language; highly recursive from simple rules [»wirtN1_1966]
Quote: separate language definition from program definition; van Wijngaarden grammars mix the two

Related Topics up

Topic: attribute grammar (9 items)
Topic: formal methods and languages (53 items)
Topic: semantic grammar
(23 items)

Updated barberCB 3/05
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