Flex
Software
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Flex is a free and open-source software alternative to lex.
It is a computer program that generates lexical analyzers.
It is frequently used as the lex implementation together with Berkeley Yacc parser generator on BSD-derived operating systems,... Wikipedia
Programming language: C
Developer(s): Vern Paxson
Initial release: around 1987; 37 years ago
License: BSD license
Operating system: Unix-like
Stable release: 2.6.4 / May 6, 2017; 6 years ago