libbison-dev - 2:3.7.5+dfsg-1 main

Bison is a general-purpose parser generator that converts a
grammar description for an LALR(1) context-free grammar into a C
program to parse that grammar. Once you are proficient with Bison, you
may use it to develop a wide range of language parsers, from those used
in simple desk calculators to complex programming languages.
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This package provides the liby.a file including functions needed by
yacc parsers.