[GHC] #5892: Compiler crash and other oddities when using RecordWildCards with record accessors not imported

[GHC]

#5892: Compiler crash and other oddities when using RecordWildCards with record
accessors not imported
------------------------------------------------+---------------------------
  Reporter:  parcs                              |          Owner:                  
      Type:  bug                                |         Status:  closed          
  Priority:  normal                             |      Milestone:                  
 Component:  Compiler                           |        Version:  7.4.1           
Resolution:  fixed                              |       Keywords:                  
        Os:  Unknown/Multiple                   |   Architecture:  Unknown/Multiple
   Failure:  Compile-time crash                 |     Difficulty:  Unknown         
  Testcase:  rename/should_fail/T5892a, T5892b  |      Blockedby:                  
  Blocking:                                     |        Related:                  
------------------------------------------------+---------------------------
Changes (by simonpj):

  * status:  new => closed
  * difficulty:  => Unknown
  * resolution:  => fixed
  * testcase:  => rename/should_fail/T5892a, T5892b


Comment:

 Good point.  I've fixed the compiler bug.

 I looked in [http://www.haskell.org/ghc/docs/latest/html/users_guide
 /syntax-extns.html#record-wildcards the documentation] and it seems clear
 enough that the ".." expands only to the ''in-scope'' fields.  So for
 example in your code
 {{{
 import Data.Tree (Tree(Node))

 foo = let rootLabel = (); subForest = [] in Node{..}
 }}}
 since there are ''no'' in-scope fields, this behaves just as if you'd said
 {{{
 import Data.Tree (Tree(Node))

 foo = let rootLabel = (); subForest = [] in Node{}
 }}}
 And I think the implementation faithfully does that.

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5892#comment:3>
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