[GHC] #10945: Typed Template Haskell splices broken in HEAD (7.11)

[GHC]

#10945: Typed Template Haskell splices broken in HEAD (7.11)
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        Reporter:  jstolarek         |                Owner:  jstolarek
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.0.1
       Component:  Template Haskell  |              Version:  7.11
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:  th/T10945
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1344
       Wiki Page:                    |
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Comment (by Jan Stolarek <jan.stolarek@…>):

 In [changeset:"1750ebc2e40bab85246717326d3d5c60f132e652/ghc"
 1750ebc2/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="1750ebc2e40bab85246717326d3d5c60f132e652"
 Reject top-level typed TH splices. Fixes #10945

 When TemplateHaskell language extension is enabled it is valid to have
 top-level expressions.  Each such expression is treated as a contents
 of a splice.  The problem arises with typed splices.  They are not valid
 at the top level and therefore we should interpret them not as a splice
 but as a top-level expression (aka. implicit splice).  So saying:

 $$foo

 is equivalent of:

 $( $$foo )

 This patch makes sure that this is indeed the case.  Until now we
 incorrectly treated typed splices as explicit splices.
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10945#comment:10>
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