CS_221 Functional Programming

Haskell and Graphics

Report on the Hugs Graphics Library

The easiest way to work with the graphics library in the linux lab (without downloading the library):

1. Insert in your .cshrc file the lines

   alias runhuggs 'runhugs -P/compsci/saturn/staff/csulrich/graphics-2.0.4/lib/x11:'

   alias huggs 'hugs -P/compsci/saturn/staff/csulrich/graphics-2.0.4/lib/x11:'

   If you work in a bash shell, then include the corresponding lines in the file .bashrc inserting = after runhuggs, huggs respectively.
2. A sample file: HelloWorld.hs
3. Run the sample file: runhuggs HelloWorld.hs
   Also try: huggs HelloWorld.hs and call main to obtain the same result.
4. The difference between runhuggs and hugs:
   • runhuggs expects as argument a filename and executes the program main (which must exist in the file).
   • huggs is used exactly like hugs (with the advantage that you may execute in addition graphics programs).
   • Probably you will find huggs more convenient to use.

Downloading the graphics library:

• Linux: graphics-2.0.4.src.tar.gz(166k),
• Windows: I'll put this here shortly (the downloading links at the hugs web page don't seem to work).

Installation instruction in linux:

1. Unpack the tar file:

   tar -xvf graphics-2.0.4.src.tar.gz

   
   

2. Installation:

   make -C graphics-2.0.4/lib/x11 system=Linux hugs_install=/usr/bin/hugs

   
   It might be necessary to replace `/usr/bin/hugs' by the actual hugs path (type `which hugs' to find out this path).

3. Test:

   runhugs -Pgraphics-2.0.4/lib/x11: graphics-2.0.4/demos/HelloWorld.hs