Gallifreyc

This is the Polyglot compiler extension for the Gallifrey language.

Repository Overview:

Package	Contents
gallifreyc	Pass scheduler
gallifreyc.ast	AST node definition & construction
gallifreyc.extension	Language dispatcher, extension objects for existing AST nodes
gallifreyc.parse	Lexer (.flex) and Parser (.ppg compiles to .cup)
gallifreyc.translate	AST rewriters
gallifreyc.types	TypeSystem and Type object overrides
gallifreyc.visit	TypeChecker & other visitors

This extension follows a similar structure as other Polyglot extensions except for a few areas:

• The singleton language dispatcher is used (not present in older Polyglot examples)
• AST nodes and extension objects are in separate packages
• Multiple rewriting passes post-typechecking, potentially generating additional source & class files

Setup Notes:

• Requires: Java 8, ant build system
• Dependencies in lib/: java_cup.jar, jflex.jar, polyglot.jar, ppg.jar, full-runtime.jar
• The first 3 can be taken from polyglot, but the latter dependency requires gallifrey-antidote; the directory containing the gallifreyc repo and the directory containing the gallifrey-antidote repo should be under the same parent directory
• To set up gallifrey-antidote: build the project, run fatjar.sh, and verify that full-runtime.jar was generated in that directory. There is an alias of full-runtime.jar inside gallifreyc/lib
• Build gallifreyc using ant
• To execute gallifreyc from the command line: java -jar lib/gallifreyc.jar -postopts -Xlint:unchecked -classpath tests/out:lib/full-runtime.jar <FILE_NAME> (the sample classpath assumes the test suite has been run already; it may be adjusted but must include full-runtime.jar, and compiled versions of Shared.java, Unique.java, InternalGallifreyException, & RunAfterTest.java from tests/.
• Useful flags: -d (set output directory), -c (don't run javac; emit .java instead of .class), -stdout (dump java AST to stdout)

Test Suite Notes:

• Requires pth (the polyglot test harness) in your classpath. The easiest way to get this is from the polyglot repo; clone it and add polyglot/bin to your path.
• Run test suite by executing test.sh inside tests/
• The test cases check that 1) gallifreyc successfully compiles the code OR throws an expected error and 2) the generated java code can compile
• Output .java and .class files are written to tests/out
• Antidote tests need to be manually run, and require both gallifrey-antidote and antidote repositories (make sure to make clean in both repositories before each run)
• To set up antidote tests: make shell to build antidote; edit the Makefile in gallifrey-antidote to include the directory where your .class files are (for test cases, tests/out), and make backend.
• To run the existing antidote tests, execute test.sh and then run the appropriate .class file inside test/out.
• Because the tests use the same output directory, avoid conflicting restriction/class names for test cases.
• ClassC is a dummy class that has several dummy methods, it is used in several test cases and can be modified to add methods for new test cases if necessary (don't change any existing methods otherwise tests will break)

Other notes/caveats/limitations:

• Restrictions should only be written for classes in the same compilation unit, due to the source code for each shared class requiring modifications to be compatible with the Gallifrey runtime
• Restriction-defined test methods cannot be overloaded, cannot overload/shadow methods of the base class, and no two restrictions may define test methods that have the same name
• Restriction-defined test methods should not access members of the class in their bodies for now (pending further testing)
• Should use wrapper classes of primitives for type annotations whenever possible; the behavior of primitives should default to local, but there may be bugs so explicitly specifying local Integer is probably safer than using int

TODOs:

• Default qualifications for stdlib (field and method instances)
• Check transition runtime behavior matches TS
• Ownership typechecking