[GHC] #14690: Pattern match failure in GHCi with :steplocal

19 Jan 2018

      #14690: Pattern match failure in GHCi with :steplocal
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           Reporter:  Philonous       |             Owner:  (none)
               Type:  bug             |            Status:  new
           Priority:  normal          |         Milestone:
          Component:  Compiler        |           Version:  8.2.2
           Keywords:                  |  Operating System:  Linux
       Architecture:  x86_64 (amd64)  |   Type of failure:  None/Unknown
          Test Case:                  |        Blocked By:
           Blocking:                  |   Related Tickets:
Differential Rev(s):                  |         Wiki Page:
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 Using steplocal after breaking on an exception leads to GHCI giving a
 pattern match error

 Minimal testcase:

 {{{
 Prelude> :set -fbreak-on-exception
 Prelude> error "abc"
 Stopped in <exception thrown>, <unknown>
 _exception :: e = _
 [<unknown>] [<unknown>] Prelude> :steplocal
 *** Exception: Pattern match failure in do expression at
 ghc/GHCi/UI.hs:3149:12-18
 }}}

 :step works as expected.

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14690
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