related,
'c' < 'b'
|domain error
On Friday, March 1, 2019, 1:03:38 p.m. EST, Raul Miller
<rauldmil...@gmail.com> wrote:
It does seem ironic that < is both "less than" and "box" but that
"less than" on boxed arguments is a domain error.
Perhaps, early on, that domain error was seen as more likely to be
useful than a problem?
(Most likely, though, doing tolerant comparisons on boxed arguments
introduced high complexity issues for an operation like "less than",
and our people who might have the insight to resolve those issues have
had other things to do...)
Thanks,
--
Raul
On Fri, Mar 1, 2019 at 12:45 PM R.E. Boss <r.e.b...@outlook.com> wrote:
>
> For comparisons we have equal (=) and not equal (~:) and less than (<) and
> larger than (>).
> I ignore min (<.) and max (>.) and less or equal (<:) and larger or equal
> (>:) since I consider them as direct derivatives of < and >. Also match (-:)
> is ignored.
>
> All four (=, ~:, < and >) have dyadic rank 0, but I am more interested in
> their differences, which, to me, are rather annoying.
> We get
> =/2 4 ?.@$ 2
> 0 0 1 1
> for obvious reasons, and likewise with the 3 other verbs.
>
> But why is the next behavior different?
> =/;/2 4 ?.@$ 2
> 0
> ~:/;/2 4 ?.@$ 2
> 1
> </;/2 4 ?.@$ 2
> |domain error
> | </;/2 4?.@$2
> >/;/2 4 ?.@$ 2
> |domain error
> | >/;/2 4?.@$2
>
> Because we can compare the boxed items, as is shown by
> /: ;/2 4 ?.@$ 2
> 0 1
>
> Needless to say also the other comparisons go wrong
> <./;/2 4 ?.@$ 2
> |domain error
> | <./;/2 4?.@$2
> <:/;/2 4 ?.@$ 2
> |domain error
> | <:/;/2 4?.@$2
>
> Of course I can circumvent the errors in one way or the other, e.g. by using
> /:, but usually that costs quite some performance.
> Is there any time soon that the techniques which are used to compare boxed
> atoms, like used in /: , will be used for < and > too?
>
>
> R.E Boss
>
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