java com.veromodo.tioa.Main [option ...] source-file ...

• -il causes the checker to generate intermediate language output
• -p causes the checker to prettyprint the first source file
• -path <dirlist> causes the checker to use <dirlist> as a search path

A grammar for the TIOA specification languages can be found in the file parser/grammar.src. The Unix command file grammar.scr generates a parser (parser.java) for this grammar using the Java Cup parser generator. The parser generator also produces the class syms.java. The package tioa.parser also contains lexers and tokenizers for the input stream, as well as classes used to construct an abstract syntax tree. The package tioa.checker contains classes for checking and attributing abstract syntax trees, as well as classes that maintain symbol tables for sorts, operators, and variables. Finally, the package tioa.util contains a prettyprinter and other utility classes.

Work needed to finish the implementation of the checker:

• The grammar needs to be modified (with error productions) so that the checker can detect more than one syntax error in a specification.
• The output routines for termNodes need to be modified so that they will print properly qualified terms that may contain shared subterms. The current implementation works now, because only renamed terms can contain shared subterms, and these renamed terms are never printed. However, renamed terms will be printed when the -lp option is implemented (and different qualifications may be needed for different instances of the shared subterms). The implementation technique can be found in the LP module unpterm.clu.

• Develop a comprehensive set of test programs for the checker.
• Do better checking of implicitly declared variables in transition parameter lists. If the type of the corresponding formal parameter for the action is not known, the error message lists all types as possible overloadings of the variable.

• Should we prohibit renamings of decimal literals?