Ocamlhi - Caml-like functional language interpreter written in Haskell

Useful files

Modified language grammar
Tests' description and known bugs

Language modifications

1. Function calls should be Ocaml-like. [Work in progress.]
2. Expressions with infix operators always have to be enclosed in brackets.
3. Static-typing with type signatures.
4. Static bindings.
5. #enable statements which modify the behaviour of the interpreter.
6. C++ style garbage collector based on shared pointers.

Naming Convention (Source)

1. eval* functions evaluate expressions.
2. apply* functions apply functions to elements and returns the result.
3. trans* functions modify the environment.
4. to*From* functions perform casting.
5. type* functions are connected with type evaluation.
6. trace* functions print to stdout.
7. make* functions generate code.
8. fv* functions are connected with static binding.
9. set* functions modify the scope properties.
10. mem* functions are responsible for memory management.

Build docker image

    make build_docker

Dealing with containers

If you want to start the container and you have not already created it use:

    make run_docker

Otherwise attach to the container:

    make start_docker

If you want to delete the container run:

    docker container rm ocamlhi

Build

    make build

Test

    make test
    python3 unittests.py [--print_failed]
    ./ocamlhi tests/good/01_Constants.ml
    ./ocamlhi -s tests/good/99_Tree.ml # TODO(?)

Style

    ./test_style.sh
    make test_style

Debugging

Use printing functions inside the code:

    pushToOstream "Checkpoint"
    traceEnvironment;

Alternatively, you can change defaultFlags in Flags.hs.

Grammar changes

If you need to update the grammar you can:

1. Modify the ocaml.fc file.
2. Run make bnfc
3. Resolve changes manually.

Issues

If the output is "Killed" you probably have exceeded timeout (tests, timeout = 1s).
You may try to run the test manually.

References

• OCaml language description
• OCaml BNF syntax
• OCamli - Ocaml interpreter in Ocaml (BSD)
• BNF converter (GPL)
• Happy - Parser generator (BSD)
• Alex - Lexical analyser generator (BSD)
• Haskell documentation - Profiling
• Stack Overflow - Why is impredicative polymorphism allowed only for functions in Haskell?
• TH - Template Haskell tutorial by Mark Karpov
• PathDB
• ruslanspivak.com - Algorithm for nesting scopes in Python
• unification-fd example
• Monadic Compilers for Programming Languages
• Polymorphism in Ocaml - Ad-hoc, parametric, inclusion/subtyping

Referenced papers

• Dezani, Mariangiola & Giannini, Paola & Zucca, Elena. (2009). The essence of static and dynamic bindings. 99-106.
• Erkok (2002). Value Recursion in Monadic Computations
• Sunil Kothari and James L. Caldwell (2007). Type Reconstruction Algorithms: A Survey
• Vytiniotis, Peyton Jones, Schrijvers, Sulzmann (2010). OutsideIn(X) Modular type inference with local assumptions
• Mark P. Jones (2000). Typing Haskell in Haskell
• Xavier Leroy (1992). Polymorphic typing of an algorithmic language
• David J. King, John Launchbury (1998). Lazy Depth-First Search and Linear Graph Algorithms in Haskell.