Yacc

Yacc is a piece of computer software that serves as the standard parser generator on Unix systems. The name is an acronym for "Yet Another Compiler Compiler." It generates a parser (the part of a compiler that tries to make sense of the input) based on a grammar written in BNF notation. Yacc generates the code for the parser in the C programming language.

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Yacc was developed by Stephen C. Johnson at AT&T for the Unix operating system. Later compatible programs were written, such as Berkeley Yacc, GNU bison, MKS yacc and Abraxas yacc (an updated version of the original AT&T version is also open source as part of Sun's OpenSolaris project). Each offer slight improvements and additional features over the original Yacc, but the concept has remained the same; Yacc has also been rewritten for other languages, including ML and Java.

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Since the parser generated by Yacc requires a lexical analyzer, it is often used in combination with a lexical analyzer generator, in most cases either Lex or the free software alternative Flex. The IEEE POSIX P1003.2 standard defines the functionality and requirements to both Lex and Yacc.

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Computer software: Computer software (or simply software) is essentially a computer program encoded in such a fashion that the program (the instruction set) contents can be changed with minimal effort. Computer software can have various functions such as controlling hardware, performing computations, communication wit...

Parser generator: REDIRECT compiler-compiler...

Yet Another: In hacker jargon, the use of 'Yet Another' as a way of padding out an acronym is fairly common. Examples include:...