Which is a parser generator?

Which is a parser generator?

A parser generator is a program that takes as input a specification of a syntax, and produces as output a procedure for recognizing that language. Historically, they are also called compiler-compilers.

What type of parser does Python use?

Making experiments. As the generated C parser is the one used by Python, this means that if something goes wrong when adding some new rules to the grammar you cannot correctly compile and execute Python anymore.

What does a parser produce?

A parser is a compiler or interpreter component that breaks data into smaller elements for easy translation into another language. A parser takes input in the form of a sequence of tokens, interactive commands, or program instructions and breaks them up into parts that can be used by other components in programming.

What is a Pratt parser?

A Pratt parser is also known as a Top-Down Operator Precedence parser, aka TDOP parser. The general algorithm was discovered and outlined by Vaughn Pratt in 1973 in his paper[1]. It differs from recursive-descent classes of parsers by associating parsing rules to tokens rather than grammar rules.

How does a PEG parser work?

PEG parsers are usually constructed as a recursive descent parser in which every rule in the grammar corresponds to a function in the program implementing the parser and the parsing expression (the “expansion” or “definition” of the rule) represents the “code” in said function.

What do bottom up parser create?

Bottom Up Parsers / Shift Reduce Parsers Build the parse tree from leaves to root. Bottom-up parsing can be defined as an attempt to reduce the input string w to the start symbol of grammar by tracing out the rightmost derivations of w in reverse.

Can EBNF parse [ISO] grammars?

The EBNF gem can also parse [ISO/EIC 14977] Grammars (ISOEBNF) to S-Expressions. The EBNF gem can also parse ABNF Grammars to S-Expressions. Inevitably while implementing a parser for some specific grammar, a developer will need greater insight into the operation of the parser.

Is there a generic EBNF parser in Ruby?

EBNF parser and generic parser generator. This is a Ruby implementation of an EBNF and [BNF][] parser and parser generator. It parses EBNF grammars to [BNF][], generates First/Follow and Branch tables for LL(1) grammars, which can be used with the stream Tokenizer and LL(1) Parser.

How does the EBNF parser work?

These rules are driven using the {EBNF::PEG::Parser} module which calls invokes the starting rule and ensures that all input is consumed. In another mode, it parses EBNF grammars to BNF, generates First/Follow and Branch tables for LL (1) grammars, which can be used with the stream Tokenizer and LL (1) Parser.

How do I convert EBNF to BNF?

For an LL (1) parser generator, the {EBNF::BNF.make_bnf} method can be used to transform the EBNF rule into a BNF rule. This allows First/Follow and other tables used by a parser to parse examples of the associated grammar.