[GHC] #8601: runghc from standard input and --ghc-args

[GHC]

#8601: runghc from standard input and --ghc-args
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       Reporter:  wuzzeb            |             Owner:
           Type:  bug               |            Status:  new
       Priority:  normal            |         Milestone:
      Component:  Compiler          |           Version:  7.6.3
       Keywords:                    |  Operating System:  Unknown/Multiple
   Architecture:  Unknown/Multiple  |   Type of failure:  None/Unknown
     Difficulty:  Unknown           |         Test Case:
     Blocked By:                    |          Blocking:
Related Tickets:                    |
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 I am trying to use runghc with a cabal sandbox, and it works when the
 haskell code is in a file like follows:

 {{{
 runghc -- -package-db --ghc-arg=.cabal-sandbox/i386-linux-
 ghc-7.6.3-packages.conf.d somefile.hs
 }}}

 But if I try and load the script from standard input (actually I am trying
 to run a GHC script from a bash script using "runghc << EOF" but it is
 easier to see if you just run from the console)

 {{{
 runghc -- -package-db --ghc-arg=.cabal-sandbox/i386-linux-
 ghc-7.6.3-packages.conf.d < somefile.hs
 }}}

 you get an error

 {{{
 .cabal-sandbox/i386-linux-ghc-7.6.3-packages.conf.d/:1:57:
     Not in scope: `main'
     Perhaps you meant `min' (imported from Prelude)
 }}}

 Looking at the utils/runghc/runghc.hs source file, what happens is inside
 the doIt function.  The first thing the doIt function does is call
 getGhcArgs which strips the --ghc-args.  Then it checks the args and sees
 there is no file, so falls into the case where it reads standard input,
 creates a temp file, and then recalls doIt.  Here is the problem, because
 the "--ghc-arg" string has already been stripped so the second call to
 doIt is where the error occurs.

 With that, I can actually get it to work with the following :)

 {{{
 runghc -- -package-db --ghc-arg=--ghc-arg=.cabal-sandbox/i386-linux-
 ghc-7.6.3-packages.conf.d < somefile.hs
 }}}

 By passing --ghc-arg= twice, it is stripped once the first time doIt is
 called and once the second time and GHC gets the correct args :)

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8601>
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