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Re: new approximately equal operators

From: Andrew Tomazos <andrewtomazos_at_[hidden]>
Date: Sun, 21 Jun 2020 21:10:45 +1000
On Sun, Jun 21, 2020 at 8:33 PM Bo Persson via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> On 2020-06-21 at 10:09, Andrew Tomazos via Std-Proposals wrote:
> > If you're interested in working in this space, I'd start by publishing a
> > survey of some popular existing C++ libraries that provide
> > floating-point approximately equal functionality - and carefully
> > analyzing and comparing how they do it and how they are used. Next step
> > would be to propose this functionality into the standard library
> > (std::approx_equal or similar), probably initially to the Numerics
> > subgroup (SG6). Once the standard library has the functionality I can
> > imagine a proposal to provide operators for it - but the latter is
> > unlikely to be accepted because new C++ operators have to meet an
> > insanely high threshold of interest for some reason. (Amusing to
> > compare other languages like Scala or Perl 6 - where arbitrary new
> > operators can be user-defined like functions)
>
> Possibly because C++ already has a crazy 17 level operator precedence
>
> https://en.cppreference.com/w/cpp/language/operator_precedence
>
> Where would you insert a bunch of user defined ones? :-)
>

Scala: https://docs.scala-lang.org/tour/operators.html#precedence

Perl 6: https://docs.raku.org/language/operators


>
>
> Bo Persson
>
>
>
> >
> > On Tue, Jun 9, 2020 at 5:55 AM Vishal Oza via Std-Proposals
> > <std-proposals_at_[hidden] <mailto:std-proposals_at_[hidden]>>
>
> > wrote:
> >
> > I was wondering if there is any interest in adding approximately
> > equal to operators into the language. The main purpose is to compare
> > floating point calculations with rounding error, however they could
> > be used for similarity of objects or fixed point rounded values as
> well.
> >
>
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Received on 2020-06-21 06:14:09