Hi Dag, this was a good suggestion, but it doesn't work. When invoking this preprocessor, GHC will run the command
runghc <source> <input> <output> PreProc. In other words, any options specified with -optF are appended at the *end* of the preprocessor arguments, not the beginning. So one can never use runghc to run a proprocessor. Thanks, -- Peter Dag Odenhall wrote: > > How about -pgmF runghc -optF PreProc? > > > On Mon, Dec 9, 2013 at 12:48 AM, Peter Selinger > <selin...@mathstat.dal.ca>wrote: > > > Thanks for the suggestion! However, it is not portable: it doesn't > > work on Windows. > > > > Similarly, giving "runhaskell ./PreProc.hs" as the preprocessor > > command to GHC doesn't work either, because GHC will try to run a > > program with that exact name (including the space), rather than > > interpreting it as a command with an argument. > > > > In addition, even on Posix systems, where the above method does work, > > it is nevertheless extremely slow: runhaskell will have to interpret > > or compile ./PreProc.hs separately for each source file, of which > > there could be many. > > > > Another solution I thought of is to include > > > > import Preproc > > > > at the beginning of Setup.hs. This way compiling Setup.hs would have > > the side effect of compiling Preproc.hs. It would not work with the > > "runhaskell Setup.hs" method, though. > > > > -- Peter > > > > Erik Hesselink wrote: > > > > > > On Sun, Dec 8, 2013 at 7:50 PM, Peter Selinger <selin...@mathstat.dal.ca> > > wrote: > > > > thanks for your reply! So say my package directory contains two files: > > > > > > > > Test.hs > > > > PreProc.hs > > > > > > > > What you are suggesting is: > > > > > > > > ghc Test.hs -F -pgmF ./PreProc > > > > > > > > However, this gives the error message: > > > > > > > > ghc: could not execute: ./PreProc > > > > > > > > And indeed, while GHC is smart enough to automatically run a > > > > preprocessor, it is not smart enough to automatically *compile* the > > > > preprocessor. So it needs to be compiled beforehand, which would be > > > > Cabal's job. > > > > > > Not per se. You could try making it executable, and prepending a line > > like: > > > > > > #!/usr/bin/env runhaskell > > > > > > That way you can run your preprocessor like a script, without compiling > > it. > > > > > > Erik > > > > > > > _______________________________________________ > > cabal-devel mailing list > > cabal-devel@haskell.org > > http://www.haskell.org/mailman/listinfo/cabal-devel > > > _______________________________________________ cabal-devel mailing list cabal-devel@haskell.org http://www.haskell.org/mailman/listinfo/cabal-devel
