[GHC] #3165: :history throws "Irrefutable pattern failed" exception

[GHC]

#3165: :history throws "Irrefutable pattern failed" exception
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Reporter:  greenrd  |          Owner:        
    Type:  bug      |         Status:  new   
Priority:  normal   |      Component:  GHCi  
 Version:  6.10.1   |       Severity:  normal
Keywords:           |       Testcase:        
      Os:  Linux    |   Architecture:  x86   
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 I am trying to use the GHCi debugger to find out why my code has a
 StackOverflow exception - but GHCi itself seems to be throwing an
 exception when I type :history:

 {{{
 (temp)[greenrd at localhost megaslurp]$ ghci Web.Twitter.Slurp
 GHCi, version 6.10.1: http://www.haskell.org/ghc/  :? for help
 Loading package ghc-prim ... linking ... done.
 Loading package integer ... linking ... done.
 Loading package base ... linking ... done.
 [1 of 1] Compiling Web.Twitter.Slurp ( Web/Twitter/Slurp.hs, interpreted )
 Loading package syb ... linking ... done.
 Loading package array-0.2.0.0 ... linking ... done.
 Loading package packedstring-0.1.0.1 ... linking ... done.
 Loading package containers-0.2.0.0 ... linking ... done.
 Loading package pretty-1.0.1.0 ... linking ... done.
 Loading package template-haskell ... linking ... done.
 Loading package mtl-1.1.0.2 ... linking ... done.
 Loading package filepath-1.1.0.1 ... linking ... done.
 Loading package old-locale-1.0.0.1 ... linking ... done.
 Loading package old-time-1.0.0.1 ... linking ... done.
 Loading package unix-2.3.1.0 ... linking ... done.
 Loading package directory-1.0.0.2 ... linking ... done.
 Loading package process-1.0.1.0 ... linking ... done.
 Loading package random-1.0.0.1 ... linking ... done.
 Loading package derive-0.1.4 ... linking ... done.
 Ok, modules loaded: Web.Twitter.Slurp.
 *Web.Twitter.Slurp> :set -fbreak-on-error
 *Web.Twitter.Slurp> :trace slurpRetry "/host/twitter-groups.csv"
 Loading package base-3.0.3.0 ... linking ... done.
 Loading package bytestring-0.9.1.4 ... linking ... done.
 Loading package parsec-2.1.0.1 ... linking ... done.
 Loading package network-2.2.0.1 ... linking ... done.
 Loading package utf8-string-0.3.4 ... linking ... done.
 Loading package json-0.4.3 ... linking ... done.
 Loading package HTTP-4000.0.5 ... linking ... done.
 Loading package binary-0.5.0.1 ... linking ... done.
 Loading package mime-0.3.0 ... linking ... done.
 Loading package csv-0.1.1 ... linking ... done.
 Loading package hs-twitter-0.2.5 ... linking ... done.
 Stopped at <exception thrown>
 _exception ::
   e = GHC.Exception.SomeException (GHC.Exception.:DException _
 (GHC.Show.:DShow ...) ....)
                                   GHC.IOBase.StackOverflow
 [<exception thrown>] *Web.Twitter.Slurp> :history
 *** Exception: main/InteractiveEval.hs:(179,13)-(183,46): Irrefutable
 pattern failed for pattern Data.Maybe.Just decl
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3165>
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