NAME

       DrIFT - a type sensitive preprocessor for Haskell

SYNOPSIS

       DrIFT [ options ...  ] file ...

DESCRIPTION

       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.

       -v, --verbose
              chatty output on stderr

       -V, --version
              show version number

       -l, --list
              list available derivations

       -L, --noline
              omit line pragmas from output

       -o FILE, --output=FILE
              output FILE

       -s name:value, --set=name:value
              set argument to value

       -r, --results-only
              output only results, do not include source file

       -g rule, --global=rule
              addition rules to apply globally

       -i, --ignore
              ignore directives in file, which is useful with -g

ENVIRONMENT

       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:
       good - /users/grad/nww/share/hugs/lib:/users/grad/nww/share/hugs/lib/hugs
       bad  - /users/grad/nww/share/hugs/lib/:/users/grad/nww/share/hugs/lib/hugs/

COPYRIGHT

       © 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.

SEE ALSO

       drift-ghc(1), ghc(1),

AUTHOR

       This manual page was written by Arjan Oosting <arjanoosting@home.nl> for the Debian system
       (but may be used by others).