[GHC] #9230: Make -fwarn-tabs the default

[GHC]

#9230: Make -fwarn-tabs the default
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        Reporter:  dfeuer            |                   Owner:  mlen
            Type:  feature request   |                  Status:  closed
        Priority:  normal            |               Milestone:  7.10.1
       Component:  Compiler          |                 Version:  7.8.2
      Resolution:  fixed             |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:  Phab:D255,
                                     |  Phab:D399
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Comment (by oerjan):

 Replying to [comment:33 beroal]:
 > What about people who use tab characters for indentation regularly? My
 code looks correct for any tab character width chosen.

 People who are sure they know what they're doing can use the `-fno-warn-
 tabs` flag.

 The reason for making this the default is that tabs trip up a ''lot'' of
 people who are new to Haskell.  It also makes their pleas for help
 ''extremely'' confusing and time-wasting on a site like Stack Overflow,
 which autoconverts tabs to spaces - with a ''different'' width rule than
 Haskell uses.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9230#comment:34>
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