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, 2000-2002. 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,
2001-2002. 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.
It is the intention that this software be "freely available" in the Gnu
and Open Source
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:
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
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
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
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