This subdirectory contains the CUP (version 0.11b) and jflex (version 1.7.0) tools used to process the scanner and parser specifications. In addition, there are some emacs and vi configuration files taken from the jflex distribution that you might find useful when editing grammar specifications.

It also contains copies of the symbol and lr_parser source files, pulled from the CUP source repository. These may be useful for reference. Parsers generated by CUP extend lr_parser, and it is possible to override methods in the CUP specification. That is sometimes useful for error handling and similar customizations (see the CUP documentation for detail). symbol and its subclasses define the tokens.

Finally, this directory contains the necessary libraries for running JUnit tests, to make it easy for you to write your own tests as you develop your compiler.

You should not attempt to compile these files (compiled versions are included in the jar files where needed), and the source versions might not correspond exactly to the compiled versions. But they should give a good idea of the interfaces and operation of these classes if that is helpful.

Otherwise there is no need to look inside this directory or change anything in it.