[GHC] #9642: LANGUAGE pragma synonyms

[GHC]

#9642: LANGUAGE pragma synonyms
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              Reporter:  dreixel     |            Owner:
                  Type:  feature     |           Status:  new
  request                            |        Milestone:
              Priority:  normal      |          Version:  7.9
             Component:  Compiler    |         Keywords:
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Unknown
  Unknown/Multiple                   |       Blocked By:
       Type of failure:              |  Related Tickets:
  None/Unknown                       |
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by nomeata):

 I like it.

 I worry that the implementation is non-trivial: After all, you’d want the
 parser to know about the pragmas, and you need the parsed module before
 knowing the import list.

 How about putting these aliases into the package database? This is loaded
 before an individual module is loaded and avoids module dependencies? I.e.
 a new stanza:
 {{{
 language PedrosHaskell
   extensions:       BangPatterns
                     EmptyDataDecls
                     FlexibleContexts
                     FlexibleInstances
 }}}
 in some dependencies’ `.cabal` file?

 (This opens the way to other `cabal` flags to be used here, e.g. compiler
 flags to load a specific plugin, which might be very useful, but let’s not
 go there with this proposal yet.)

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9642#comment:7>
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