The most recent revision of this manual can always be found at http://www.ccs.neu.edu/home/will/Larceny/CommonLarceny/user-manual.html.

Background

What Is Common Larceny?

Common Larceny is a variant of Larceny, a simple and efficient run-time system for Scheme. It is built to run on the ECMA Common Language Infrastructure (CLI). In Common Larceny, Scheme code is compiled to Common Intermediate Language, and is then assembled into bytecode for execution by native just-in-time (JIT) compilers.

When used in conjunction with Microsoft's .NET Framework, which includes an implementation of the CLI, the Common Language Runtime, Common Larceny provides an interface to the .NET Framework class library, allowing developers to take full advantage of dozens of predefined classes designed to facilitate application development.

Who Developed Common Larceny?

Common Larceny was initially developed between 2002 and 2004 by Ryan Culpepper, Joe Marshall, Dale Vaillancourt, and others under the direction of Will Clinger and Matthias Felleisen at Northeastern University. Felix Klock, Jesse Tov, and Chris Burns have contributed to the latest development of Common Larceny.

Obtaining Common Larceny

The easiest way to start using Common Larceny is to download a binary distribution bundle. Each bundle contains a Common Larceny executable file, and the libraries required by the executable. If you'd like to build from source, you can do that, too. However, first you must ensure that your system meets certain requirements.

System Requirements

Currently, this software is distributed for Windows on Intel x86 machines, Microsoft .NET Framework 2.0.

Common Larceny may work on other platforms (e.g. Mac OS X with the Mono Framework 1.1) but we do not yet provide support for those systems.

Common Language Infrastructure

Common Larceny requires the Common Language Infrastructure. It is known to work with the Microsoft .NET Framework implementation, but the v0.93 release does not work with Mono. It is doubtful whether the v0.93 release works with DotGNU Portable.NET or Microsoft Shared Source CLI (Rotor), but it hasn't been tried.

When using the Microsoft .NET Framework implementation of the CLI, you only need the .NET redistributable package, but the .NET SDK contains a much richer set of utilities and documentation.

Environment Variables

Common Larceny requires you to have the environment variable LARCENY_ROOT defined as the root directory of your larceny distribution, e.g. C:\Larceny\.

For more information on managing environment variables in Windows XP, see Microsoft Knowledge Base Article 310519.

Binary Distribution

Choose one of these binary distribution bundles:

The CommonLarceny.exe executable is a console program. When it is started, it will print a number of diagnostic lines and then enter a read-eval-print loop.

Note: The distributed bundles also include the Larceny.exe executable. This is not a standalone application so no attempt should be made to run the file on its own.

Source Distribution

If you would like to build Common Larceny from source, download the source distribution (Gzipped TAR File). Once you have downloaded the source distribution, the instructions below should enable you to build Common Larceny yourself.

Building from Source

Setup

To build Larceny from source, you will need a working Scheme system. You can build Common Larceny with another version of Larceny, or a different Scheme system like PLT's MzScheme.

You will also need to have a couple of executable programs available in your path. You may need to edit src\Rts\DotNet\makefile to use appropriate programs on your system.

Once you have ensured the above requirements are met, start your host Scheme system, and change to the root of the Larceny distribution, if necessary. The current-directory procedure should do the trick. Then, load the configuration file for Common Larceny: (load "src/Build/dotnet.sch")

Next, you need to inform the build tool of the specifics of the host environment. Invoke larceny-setup with three or four arguments:

> (larceny-setup <host-scheme> <os> <endianness> <codegen-options>)

where:

For example, to build under MzScheme on a Windows machine, using Microsoft's C/C++ Compiler, you would use:

> (larceny-setup "MzScheme" 'win32 'little 'use-cl)

After setting up the environment for building Larceny, evaluate the following:

> (build-config-files)
> (load-compiler)

The first procedure builds the config files (Rts\*.cfg), and the second loads the Twobit compiler. You can't load the compiler until after you have run larceny-setup and build-config-files.

The .NET Heap

The next step involves building the .NET heap. After loading the compiler in the previous step, simply evaluate:

> (make-dotnet-heap)

This procedure loads the Scheme files needed to build the .NET heap and compiles and assembles their contained code to MSIL code in three stages. First it compiles Scheme code to MacScheme code (.lap files), then assembles the MacScheme code into s-expressions representing MSIL code, (.lop files), and finally dumps these s-expressions as raw MSIL code (.code-il files).

Evaluating make-dotnet-heap produces a file in the root of the Larceny distribution, dotnet.heap.exe. This is the executable file that you will run to load Common Larceny. In bundled distributions, we rename this to CommonLarceny.exe.

The Runtime System

Lastly, you will need to build the runtime system:

> (build-runtime-system)

This procedure will create Scheme.dll in the src\Rts\DotNet directory. The Scheme.dll library contains the classes that make up the Common Larceny runtime. Copy Scheme.dll into the root directory of the Larceny Distribution.

You should now have a working copy of Common Larceny in your LARCENY_ROOT directory. Rename dotnet.heap.exe to CommonLarceny.exe (not necessary but suggested) and run it to enter the interactive read-eval-print loop.

CompileOnLoad

Running the CommonLarceny.exe executable alone loads Common Larceny as an interpreted Scheme system. It is also possible to load Common Larceny so that it compiles Scheme code upon load. This creates slightly longer load times, but can improves execution times by quite a bit, so some find the CompileOnLoad version of Common Larceny more useful in certain situations.

You can build the fast-loading (.fasl) and .exe files used to invoke the CompileOnLoad version of Common Larceny. To do this, after building the heap and the runtime-system, run:

> (build-larceny)

This will create new files in the root of your Common Larceny distribution, namely Larceny.exe and Larceny.fasl. These files are required to run the CompileOnLoad version of Common Larceny.

To use the CompileOnLoad version of Common Larceny, invoke the runtime with:

%LARCENY_ROOT%\CommonLarceny.exe -- Larceny.fasl.

Using Common Larceny

Compiling Code to Run within Common Larceny

The compiler can also be used to compile code for loading into the Common Larceny interpreter. This allows you to run programs at compiled speeds without building the code into the larceny executable.

Load the compiler using the same steps as above:

> (load "Util/dotnet.sch")
> (larceny-setup <host-scheme> <os> <endianness> <codegen-options>)
> (load-compiler)

The compiler is now loaded, and you can use the following procedures:

;; build-application : string (listof string) -> void
;; Given an application name and a list of LOP files, creates
;; an EXE file and a FASL file (each LOP file must have a
;; corresponding MANIFEST file).
;; compile-application : string (listof string) -> void
;; Given an application name and a list of scheme source files,
;; creates an EXE file and a FASL file.

For example:

> (compile-application "EvenAndOdd" (list "even.sch" "odd.sch"))
> (load "EvenAndOdd.fasl")

or

> (compile313 "even.sch")
> (compile313 "odd.sch")
> (assemble313 "even.lap")
> (assemble313 "odd.lap")
> (build-application "EvenAndOdd" (list "even.lop" "odd.lop"))

Note that the first string you supply to build-application or create-application should have no file extension, and you only load the resulting .fasl file (as in invoking the CompileOnLoad feature of Common Larceny), which must be in the current directory.

Any Scheme system which can run the compiler can be used to compile the applications, but of course the resulting FASL files must be loaded by the Common Larceny interpreter.