Set Theory
More abstract view of abstract syntax
- non-terminal names set of phrases specified by corresponding BNF rule - Expression, Op, Numeral
- Rules replaced by syntax builder operations, one for each form of rule.
- Numeral-exp: Numeral -> Expression
- Compound-exp:
- Expression x Op x Expression -> Expression
- Bracket-exp:Expression -> Expression
- Terminal words replaced by constants
Words and derivation trees replaced by sets and operations.