[GHC] #9534: IEEE Standard 754 for Binary Floating-Point Arithmetic by Prof. W. Kahan, UCB

[GHC]

#9534: IEEE Standard 754 for Binary Floating-Point Arithmetic by Prof. W. Kahan,
UCB
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              Reporter:  jrp         |            Owner:
                  Type:  task        |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Test Suite  |          Version:  7.8.3
            Resolution:              |         Keywords:  IEEE754
      Operating System:              |     Architecture:  Unknown/Multiple
  Unknown/Multiple                   |       Difficulty:  Moderate (less
       Type of failure:  Incorrect   |  than a day)
  result at runtime                  |       Blocked By:
             Test Case:              |  Related Tickets:
              Blocking:              |
Differential Revisions:              |
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Comment (by carter):

 1. IEEE 2008 defines a total order
  2. yes we can provide different min/max for floating things, BUT those
 arent the min/max that come with Ord, its trivial to define a floating
 only version min or max that has the alternative behaviors, whats less
 trivial is fixing the specified semantics of the haskell side. I've spoken
 with the various folks who would actually need to vote on a proposal via
 the libraries list, and because theres no canonicity of any of the
 choices, there'll be enough  disagreement that the status quo will stay as
 is.

 I'd love to get the nan poisoning variant to be the new default, but we'd
 need a good canonicity story for making that so.

 if we just did minPoison and minMissing, no one will use them (who
 wouldn't be rolling their own anyways), and we'd have to newtype
 float/double to give alt min/max ord definitions.

 its a mess, and we need a clear canonicity argument to change up the
 behavior though.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9534#comment:5>
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