[GHC] #12641: Indentation works differently for multi-way if than for guards when using comma-separate view patterns

[GHC]

#12641: Indentation works differently for multi-way if than for guards when using
comma-separate view patterns
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        Reporter:  ahmadsalim        |                Owner:
            Type:  bug               |               Status:  closed
        Priority:  lowest            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
  (Parser)                           |
      Resolution:  invalid           |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by goldfire):

 * status:  new => closed
 * resolution:   => invalid


Comment:

 This is by design. Note that the
 [https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/glasgow_exts.html
 #multi-way-if-expressions manual] says that a multi-way `if` introduces a
 layout context. This is unlike normal pattern guards, which do not need
 layout for disambiguation of nesting.

 Personally, I've never liked this design choice, but I don't have a better
 one to suggest (then or now). There is some recent discussion
 [https://github.com/haskell/rfcs/pull/4 here].

 In any case, there's no misbehavior here, so I am closing. Thanks very
 much for reporting, however!

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12641#comment:1>
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