bison

Bison is a popular command line tool used for generating fast and efficient parsers. It is primarily used in conjunction with the GNU Project's parser generator tool, yacc. Bison is also known as "GNU Bison" due to its association with the GNU Project.

With Bison, you can specify a grammar for a programming language, data language, or other formal language, and generate a parser to analyze the structure of input that conforms to the grammar. It is particularly useful for implementing compilers and interpreters for programming languages.

Bison generates LALR(1) parsers, which are robust and efficient. It uses a language similar to C to specify the grammar rules and associated actions. Bison also supports various features like automatic syntax error reporting, semantic value types, and semantic actions.

It is worth noting that Bison is primarily a parser generator and does not handle lexical analysis. Therefore, it is commonly used in conjunction with tools like Flex, which generate lexical analyzers, forming a complete parser.

Bison is available under the GNU General Public License (GPL) and is a popular tool among developers for implementing parsers due to its efficiency, flexibility, and widespread support.