[GHC] #13600: surprising error message with bang pattern

[GHC]

#13600: surprising error message with bang pattern
-------------------------------------+-------------------------------------
        Reporter:  andrewufrank      |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.2
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:  x86_64
 Type of failure:  Poor/confusing    |  (amd64)
  error message                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by andrewufrank):

 Thank you very much for the clarification. As i said, i have not much
 experience with bang patterns and did not see in the manual the hint that
 I would have to turn on an extension. Perhaps somebody could revise the
 relevant parts of the ghc docs.
 andrew

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13600#comment:3>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler