MLton runs on a variety of platforms and is distributed in both source and binary form. The format for the binary package depends on the platform. The binary package will install under /usr or /usr/local, depending on the platform. A .tgz or .tbz binary package should be extracted in the root directory. If you install MLton somewhere else, you must set the lib variable in the /usr/bin/mlton script to the directory that contains the libraries (/usr/lib/mlton by default).

MLton requires that you have the GNU multiprecision library installed on your machine. MLton must be able to find both the gmp.h include file and the libgmp.a (or or libgmp.dylib) library. If you see the error message gmp.h: No such file or directory, you should copy gmp.h to /usr/lib/mlton/self/include. If you see the error message /usr/bin/ld: cannot find -lgmp, you should add a -link-opt -L argument in the /usr/bin/mlton script so that the linker can find libgmp. If, for example, libgmp.a is in /tmp, then add -link-opt -L/tmp.

Installation of MLton creates the following files and directories.

  • /usr/bin/mllex

    The MLLex lexer generator.

  • /usr/bin/mlnlffigen

    The ML-NLFFI tool.

  • /usr/bin/mlprof

    A Profiling tool.

  • /usr/bin/mlton

    A script to call the compiler. This script may be moved anywhere, however, it makes use of files in /usr/lib/mlton.

  • /usr/bin/mlyacc

    The MLYacc parser generator.

  • /usr/lib/mlton

    Directory containing libraries and include files needed during compilation.

  • /usr/share/man/man1/mllex.1, mlnlffigen.1, mlprof.1, mlton.1, mlyacc.1

    Man pages.

  • /usr/share/doc/mlton

    Directory containing the user guide for MLton, mllex, and mlyacc, as well as example SML programs (in the examples dir), and license information.

Hello, World!

Once you have installed MLton, create a file called hello-world.sml with the following contents.

print "Hello, world!\n";

Now create an executable, hello-world, with the following command.

mlton hello-world.sml

You can now run hello-world to verify that it works. There are more small examples in /usr/share/doc/mlton/examples.

Installation on Cygwin

When installing the Cygwin tgz, you should use Cygwin’s bash and tar. The use of an archiving tool that is not aware of Cygwin’s mounts will put the files in the wrong place.