[GHC] #4836: literate markdown not handled correctly by unlit

[GHC]

#4836: literate markdown not handled correctly by unlit
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        Reporter:  guest                      |            Owner:
            Type:  bug                        |           Status:  new
        Priority:  low                        |        Milestone:  7.6.2
       Component:  Compiler                   |          Version:  7.0.1
      Resolution:                             |         Keywords:
Operating System:  Unknown/Multiple           |     Architecture:
 Type of failure:  GHC rejects valid program  |  Unknown/Multiple
       Test Case:                             |       Difficulty:  Unknown
        Blocking:                             |       Blocked By:
                                              |  Related Tickets:  #7120
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Comment (by elliottt):

 Moving CPP after unlit solves the problem with the sections defined by #,
 but it doesn't change the fact that in markdown, bird track blocks are
 actually quotations, not code [1].

 What about this as a compromise (assuming my patch gets accepted): move
 unlit before CPP, to avoid problems with #, and keep the separate
 processing for .md/.markdown, allowing the distinction between bird tracks
 and code blocks in markdown.  This way, you can write markdown in a .lhs
 file and use bird tracks for code blocks, and I can write haskell in a .md
 file using fenced code blocks, and still be able to write quotation
 blocks.

 [1] http://daringfireball.net/projects/markdown/syntax#blockquote

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/4836#comment:17>
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