The HTk home page.

What's HTk?

HTk is an encapsulation of the graphical user interface toolkit and library Tcl/Tk for the functional programming language Haskell. It allows the creation of high-quality graphical user interfaces within Haskell in a typed, abstract, and portable manner, as HTk is known to run under Linux, Solaris, FreeBSD, Windows 98, Windows 2k, and will probably run under many other POSIX systems as well.

Features include

abstract event handling,
support of nearly all of Tk's features:
- the usual GUI elements such as buttons, menus, list boxes, &c;
- canvasses to draw on;
- text widgets for hypertext and forms;
a toolkit of useful interface elements and dialog windows,
support for Tix, the Tk Interace eXtension, with features such as notebooks and paned windows.

HTk is easy to use; for example, here is the infamous incrementing button example:

module Main where

import HTk

main :: IO ()
main = 
 do main <- initHTk []
    b <- newButton main [text "*"]
    pack b []
    cl <- clicked b
    let count :: Int-> Event ()
        count n = 
          do cl >>> (b # text n)
             count (n+1)
    spawnEvent (count 1)
    finishHTk

Download and Documentation

Here, you can

read A Short Introduction to HTk (PDF, PS, HTML [ugly])
A short, readable introduction for the HTk neophyte. Read this first!
find out how to download and install binary bundles, documentation or the source for HTk.
browse the HTk modules
read "Verkapselung von Tk-Objekten für HTk", a technical manual describing how HTk encapsulates Tk. (PDF, PS, HTML).

System requirements

You'll need the following software to run HTk:

The Glasgow Haskell Compiler, Version 5.02.3 or later;
Tcl/Tk (Version 8.0 or later; 8.1.1 or later for Windows) or Tix;
An operating system on which these two run, such as
- Windows 98 or 2000 or similar, or
- Linux, FreeBSD or Solaris (other POSIX-systems may work as well)

Problems and Troubleshooting

If you have trouble with HTk, please do not hesitate to get in touch with us (see below). We will try to help, but we can only fix problems that we know about.

We keep a list of known problems here.

Current Status

Currently, HTk is "orphanware" - while still being used and e.g. ported to later versions of the GHC if it is not too much trouble, it is not actively developed, and new releases are sparse. Its future prospects are uncertain. Use at your own peril.

Contact and Authors

If you have any questions or request, please get in touch with us at uniform@informatik.uni-bremen.de.

The principal designer of HTk was Einar Karlsen, based on GoferTk. The event handling is due to George Russell. Andree Lüdtke, together with Christoph Lüth, ported HTk to its present form.

Christoph Lueth

Last modified: Wed Mar 22 16:11:08 CET 2006