ANTLR (ANother Tool for Language Recognition) is a language tool that provides a framework for constructing recognizers, compilers, and translators from grammatical descriptions containing C++, Java, or Sather actions. It is similar to the popular compiler generator YACC, however ANTLR is much more powerful and easy to use. ANTLR-produced parsers are not only highly efficient, but are both human-readable and human-debuggable (especially with the interactive ParseView debugging tool). ANTLR can generate parsers, lexers, and tree-parsers in either C++, Java, or Sather. ANTLR is currently written in Java.
Redet is a tool for developing and executing regular expressions using any of more than 50 search programs, editors, and programming languages, intended both for developing regular expressions for use elsewhere and as a search tool in its own right. For each program in each locale, a palette showing the available constructs is provided. The properties of each program are determined by runtime tests, which guarantees that they will be correct for the program version and locale. Additional features include persistent history, extensive help, a variety of character entry tools, and the ability to change locale while running. Redet is highly configurable and fully supports Unicode.
pyPEG is a quick and easy solution for creating a parser in Python programs. pyPEG uses a PEG language in Python data structures to parse, so it can be used dynamically to parse nearly every context free language. The output is a plain Python data structure called pyAST, or, as an alternative, XML.
The GCC XML Tree Node Introspector project consists of a patch to the gcc compiler to output the internal compiler tree nodes in RDF/XML and programs to process that RDF/XML. The tree nodes are complex data structures which represent the source code inside the compiler. Through these tree nodes, users are able to extract information from their programs that would be otherwise very difficult to obtain. Modules exist to store these nodes in Redland RDF using a Berkley database. The long-term goal of the project is create a high-level API that will make the programmatic manipulation of programs easier than it is now.