molasses

molasses aims to allow the SML/NJ Compilation and Library Manager (CM) to support ML Basis (MLB) files.

Usage

First make sure you clone this repo including submodules. The command should something like this:

git clone --recurse-submodules -j8 https://github.com/T-Brick/molasses

If you have MLton installed, you can build molasses using make molasses, then passing in a MLB file to the executable:

make
./molasses test/either/either.mlb

This will generate some files in the test/either/.molasses directory. Using CM to load the molasses-sources1.cm file will load all the files into SML/NJ. To use the REPL, you can also pass in the --repl flag, which will generate the appropriate files and launch the SML/NJ REPL (using the command rlwrap sml), with the appropriate toplevel declarations already loaded.

If you only have SML/NJ installed, you can load molasses by running:

make repl

This will load an SML/NJ REPL with all of Molasses already loaded. Running this will also generate a heap image molasses-repl.arch-opsys. You can then use this heap image to load the SML/NJ REPL with Molasses anywhere by running:

sml @SMLload=molasses-repl

This should open the SML/NJ REPL with molasses loaded in. You can then use the Molasses structure to generate molasses files. The MolassesNJ structure may be used for generating heap images. Also, the implementation defined use : string -> unit has been defined to use Molasses.

Mapping Specific MLB Files

It maybe the case that there are specific libraries that you already have CM's for, and thus making converting them unnecessary. Molasses provides a way to map specific files in MLB to a pre-defined CM counterpart.

The file example-libmap demonstrates how to construct a mapping (in this case, the example is the SML basis, which is already loaded by default). The first line in the file consists of a list of space separated MLB Path Variables, which if they appear will trigger a lookup. The remaining lines are the file path as it appears in the MLB file, followed by one or more spaces, then the corresponding CM equivalent of the file.

Limitations

Currently there are a number of limitations, that will hopefully be reduced in the future:

• MLB: files with annotation declarations, open declarations, and basis declarations/expressions are not supported.
• SML: Top-level open declarations are not supported.
• SML: Top-level abstype declarations are not supported.
• Most NJ language extensions are not supported.
• The MLton structure is not supported.

Naming

The name of this project follows a similar convention as seen in millet and mulligan. Namely, molasses has the letters M and L in it and in the same order as Standard ML. Also, molasses is sticky and this "sticks" two compliation systems together.