Graphics Lib

Note: The SOEGraphics library is slightly incompatible with the latest release of Hugs, so I am currently recommending the use of the previous release of Hugs until we can straighten things out. You can download SOEGraphics (and other SOE code) and the previous release of Hugs from here:

http://cvs.haskell.org/Hugs/pages/downloading-Nov2002.htm

instead of from the website listed below.

Sorry for the inconvenience,

Paul Hudak
February, 2004

If you are using Hugs to run your Haskell programs, a self-installing download of all software needed to run any program in The Haskell School of Expression is available from the Hugs website. This download includes all of the needed graphics and MIDI code, and is packaged for both Windows and Unix/Linux.

The code used in The Haskell School of Expression relies on a specific graphics module called SOEGraphics, which in turn depends on the Haskell Graphics Library (HGL). The source code also depends on a small library of MIDI code to support computer music. The download referenced above packages all of this together with the text's source code.

Note 1: The current release of Hugs fails to properly load one of Haskell's standard libraries that is used by SOE (this is a problem with Hugs, not SOE). If you get the error:

    ERROR "C:\Program Files\Hugs98\lib\exts\MarshalUtils.hs":2 -
    Syntax error in module definition (unexpected keyword "with
    "; possible cause: -W option not used.)

then simply type:

   :set -W

at the Hugs prompt, and reload the files.

Note 2: the code in the text was developed under Windows. Although all examples have been successfully tested under Linux, the Windows version is likely to be the most robust. The Linux version has not been tested on many programs besides those in the text.

Bugs in the SOEGraphics module should be reported to both Alastair Reid at reid@cs.utah.edu and Paul Hudak at paul.hudak@yale.edu.