ANTLR - ANTLR, ANother Tool for Language Recognition, is a language tool that provides a framework for...

Ragel - Ragel compiles executable finite state machines from regular languages.

textX - 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.

Bison - GNU Bison, commonly known as Bison, is a parser generator that is part of the GNU Project.

Eclipse Xtext - The website of Eclipse Xtext, an open-source framework for development of programming languages and domain-specific languages

Owl parser generator - Efficient and understandable parser generator.