Bison is described as 'GNU Bison, commonly known as Bison, is a parser generator that is part of the GNU Project' and is an app in the Development category. There are three alternatives to Bison for Linux, Mac and Windows. The best alternative is ANTLR, which is both free and Open Source. Other great apps like Bison are textX (Free, Open Source) and Owl parser generator (Free, Open Source).
ANTLR, ANother Tool for Language Recognition, is a language tool that provides a framework for constructing recognizers, interpreters, compilers, and translators from grammatical descriptions containing actions in a variety of target languages.
textX is a meta-language for building Domain-Specific Languages (DSLs) in Python. It is inspired by Xtext. It will help you build your textual language easily. You can invent your own language or build a support for an existing textual language.