# Hat copyright information

Development of the Hat tracing system was mainly funded by the UK's Engineering and Physical Sciences Research Council, grant number EPSRC GR/M81953. The University of York, RWTH Aachen, and Microsoft Research (Cambridge) also contributed.

The source code of the hat-trans program is copyright © Olaf Chitil and Malcolm Wallace, 2000-2003. Part of this tool is based on the front end of the nhc98 compiler, and those parts are copyright © Niklas Röjemo, 1991-1998. Parts are also based on earlier work on tracing transformations, copyright © Jan Sparud and Colin Runciman, 1996-1997.

The hat-observe, hat-detect, and hat-trail browsing tools are copyright © Malcolm Wallace and Olaf Chitil, 2001-2003. The hat-observe and hat-detect browsing tools are based on earlier tools of the same name, copyright © Thorsten Brehm, 2001.

The hat-stack tool is copyright © Malcolm Wallace, 2001-2002.

The hat-check tool is copyright © Colin Runciman and Malcolm Wallace, 2001-2002.

### LICENCE

It is the intention that this software be "freely available" in the Gnu (`http://www.gnu.org/`) and Open Source (`http://www.opensource.org/`) traditions. The following is a brief statement of the rights and restrictions attached to this software distribution. It is a preliminary licence; we may modify the terms and conditions at a later date. Any successor to this licence may, when published, be applied to this software as an alternative to the current terms, if you wish.

If you are not sure about any of the terms of this licence, please contact us to discuss your requirements. (Primary contact: Malcolm.Wallace@cs.york.ac.uk)

You may use, re-distribute, and modify this software, but you must not alter or remove these copyright notices. You may add your own additional copyright notices for any modifications to this software that you distribute. (Any modifications must be provided - at least - in source form, must be described in the documentation, and you must clearly indicate that the software has been modified, for instance by changing the name of the executable or its version number, or by some other method.)

You must not restrict anyone else's rights to use, re-distribute or modify this software. Distributions of standard or modified versions of this software must retain this licence (or its successor).

In addition, you are explicitly granted the right to re-use parts of this software in the creation of new software, without having to place the new software under this or any other licence, provided that:

- the new software does not have the same name as this software, but
- you clearly acknowledge which code you have re-used from this software,
- you retain the relevant copyright notices, and
- you indicate to users where they can freely obtain a standard version of this software.

Programs, object files, and intermediate files produced as output by this software do not fall under this copyright statement and are not governed by the terms of this licence. You are free to use them (or restrict their use) as you like.

UNLESS OTHERWISE STATED IN WRITING, THIS SOFTWARE IS SUPPLIED "AS IS" AND WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. NEITHER THE AUTHORS, COPYRIGHT HOLDERS, NOR ANY OTHER PARTY WHO REDISTRIBUTES THIS SOFTWARE SHALL BE LIABLE FOR DAMAGES, HOWSOEVER CAUSED, ARISING OUT OF THE USE OF THIS SOFTWARE. USE AT YOUR OWN RISK.

The latest updates to these pages are available on the WWW from `http://www.haskell.org/hat/`
`http://www.cs.york.ac.uk/fp/hat/`

This page last updated: 13th March 2003
York Functional Programming Group