DrIFT - a type sensitive preprocessor for Haskell
DrIFT [ options ... ] file ...
It extracts type declarations and directives from modules. The
directives cause rules to be fired on the parsed type declarations,
generating new code which is then appended to the bottom of the input
file. The rules are expressed as Haskell code, and it is intended that
the user can add new rules as required.
DrIFT automates instance derivation for classes that aren’t supported
by the standard compilers. In addition, instances can be produced in
separate modules to that containing the type declaration. This allows
instances to be derived for a type after the original module has been
compiled. As a bonus, simple utility functions can also be produced
from a type.
chatty output on stderr
show version number
list available derivations
omit line pragmas from output
-o FILE, --output=FILE
-s name:value, --set=name:value
set argument to value
output only results, do not include source file
-g rule, --global=rule
addition rules to apply globally
ignore directives in file, which is useful with -g
The environment variable DERIVEPATH can be used to declare a list of
directories which contain the modules and/or interfaces that define the
additional classes you wish to derive from. DrIFT is quite fussy about
the format of the DERIVEPATH variable. The directory list should have
the following format:
* each path should be separated by ‘:’
* no space inserted anywhere
* no final ‘/’ on the end of a path
Examples of DERIVEPATH settings:
© 2002 – 2004 DrIFT contributors
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
This manual page was written by Arjan Oosting <email@example.com>
for the Debian system (but may be used by others).