Re: [GHC] #9988: Remove fun_id, is_infix from FunBind, as they are now in Match

15 Jan 2015

      #9988: Remove fun_id, is_infix from FunBind, as they are now in Match
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        Reporter:  alanz             |                   Owner:  alanz
            Type:  task              |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1-rc1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
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Description changed by alanz:

Old description:
...
One of the changes Phab:D538 introduced is to add m_fun_id_infix to Match
{{{#!hs
data Match id body
  = Match {
        m_fun_id_infix :: (Maybe (Located id,Bool)),
          -- fun_id and fun_infix for functions with multiple equations
          -- only present for a RdrName. See note [fun_id in Match]
        m_pats :: [LPat id], -- The patterns
        m_type :: (Maybe (LHsType id)),
                                 -- A type signature for the result of
the match
                                 -- Nothing after typechecking
        m_grhss :: (GRHSs id body)
  } deriving (Typeable)
}}}
This was done to track the individual locations and fixity of the fun_id
for each of the defining equations for a function when there are more
than one.
For example, the function (&&&) is defined with some prefix and some
infix equations below.
{{{#!hs
(&&&  ) [] [] =  []
xs    &&&   [] =  xs
(  &&&  ) [] ys =  ys
}}}
This means that the fun_id / is_infix is now superfluous in the FunBind.
This has not been removed as a potentially risky change just before 7.10
RC2, and so must be done after.
This ticket captures that task.
New description:

 One of the changes Phab:D538 introduced is to add m_fun_id_infix to Match

 {{{#!hs
 data Match id body
   = Match {
         m_fun_id_infix :: (Maybe (Located id,Bool)),
           -- fun_id and fun_infix for functions with multiple equations
           -- only present for a RdrName. See note [fun_id in Match]
         m_pats :: [LPat id], -- The patterns
         m_type :: (Maybe (LHsType id)),
                                  -- A type signature for the result of the
 match
                                  -- Nothing after typechecking
         m_grhss :: (GRHSs id body)
   } deriving (Typeable)
 }}}

 This was done to track the individual locations and fixity of the fun_id
 for each of the defining equations for a function when there are more than
 one.

 For example, the function (&&&) is defined with some prefix and some infix
 equations below.

 {{{#!hs

 (&&&  ) [] [] =  []
 xs    &&&   [] =  xs
 (  &&&  ) [] ys =  ys
 }}}

 This means that the fun_id / is_infix is now superfluous in the FunBind.
 This has not been removed as a potentially risky change just before 7.10
 RC2, and so must be done after.

 This ticket captures that task, which includes processing these fields
 through the renamer and beyond.

--

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9988#comment:2
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