Since I started programming in Haskell a few years ago I have been using if-then-else in that manner without indentation and I never knew about this extension. I thought this is how it works. It seems this is the default now. But, I remember encountering an error in an older compiler version once and then I figured the my style was accepted in newer compiler versions only.
-harendra On 9 February 2018 at 08:08, Brandon Allbery <allber...@gmail.com> wrote: > Huh. I wonder if a section went missing; seems like none of the extensions > that alter or relax layout are documented currently. > (AlternativeLayoutRule, AlternativeLayoutRuleTransitional, > DoAndIfThenElse, NondecreasingIndentation, RelaxedLayout) > > IIRC DoAndIfThenElse relaxes a condition implied by layout but that > normally only matters in "do": that if you break it into multiple lines, > the "then" and "else" must be indented farther than the "if" or layout will > consider them distinct new expressions (and thereby syntax errors). > > On Thu, Feb 8, 2018 at 9:24 PM, Harendra Kumar <harendra.ku...@gmail.com> > wrote: > >> Hi, >> >> I recently found a mention of DoAndIfThenElse extension somewhere. I >> looked inside the ghc user guide and could not find any such extension. >> Then I looked in the ghc man page, no mention. I googled and found a very >> sparse references to it here and there. Then I tried using the extension >> with ghc and ghc seems to accept it. What's the story behind this, why is >> it not documented but accepted? >> >> thanks, >> harendra >> >> _______________________________________________ >> ghc-devs mailing list >> ghc-devs@haskell.org >> http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs >> >> > > > -- > brandon s allbery kf8nh sine nomine > associates > allber...@gmail.com > ballb...@sinenomine.net > unix, openafs, kerberos, infrastructure, xmonad > http://sinenomine.net >
_______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs
