Formal Languages and Translators: Difference between revisions

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  <symbol> ::= expression
  <symbol> ::= expression
where <symbol> is a nonterminal, and expression consists of one or more sequence of symbols. The expression may contain vertical bars '|' indicating a choice.


===Extended Backus-Naur form EBNF===
===Extended Backus-Naur form EBNF===

Revision as of 23:33, 7 June 2018

Internal

Formal Grammars

https://en.wikipedia.org/wiki/Formal_grammar

A set of production rules that describe all possible strings in a given formal language. The rules describe how to form strings from the language's alphabet that are valid according to the language syntax. The grammar does not describe the meaning of strings, or what can be done with them in whatever context, only their form.

Context-Free Grammar

A context-free grammar is a grammar in which the left-hand side of each production rule consists of only a single nonterminal symbol. A popular notation for context-free grammar is Backus-Naur (BNF).

Backus-Naur Form BNF

https://en.wikipedia.org/wiki/Backus–Naur_form

Backus-Naur form is notation technique for context-free grammars that is used to describe the syntax of languages used in computing.

A BNF specification is a set of derivation rules, written as:

<symbol> ::= expression

where <symbol> is a nonterminal, and expression consists of one or more sequence of symbols. The expression may contain vertical bars '|' indicating a choice.

Extended Backus-Naur form EBNF

https://en.wikipedia.org/wiki/Extended_Backus–Naur_form

Syntax Tree

Parser Generators

ANTLR