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Re: stolen uint's

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From:
ToddAndMargo via perl6-users
Date:
January 29, 2020 00:46
Subject:
Re: stolen uint's
Message ID:
3161a2d3-0c50-cb0d-6d39-80db960a543d@zoho.com
On 2020-01-28 16:30, Trey Harris wrote:
> On Tue, Jan 28, 2020 at 19:06 ToddAndMargo via perl6-users 
> <perl6-users@perl.org <mailto:perl6-users@perl.org>> wrote:
> 
>     On 2020-01-28 15:37, Trey Harris wrote:
>      >
>      >
>      > On Tue, Jan 28, 2020 at 18:09 ToddAndMargo via perl6-users
>      > <perl6-users@perl.org <mailto:perl6-users@perl.org>
>     <mailto:perl6-users@perl.org <mailto:perl6-users@perl.org>>> wrote:
>      >
>      >     Observer effect (physics)
>      > https://en.wikipedia.org/wiki/Observer_effect_(physics)
>      >
>      >           In physics, the observer effect is the theory that
>      >           the mere observation of a phenomenon inevitably
>      >           changes that phenomenon ... An especially unusual
>      >           version of the observer effect occurs in quantum
>      >           mechanics, as best demonstrated by the double-slit
>      >           experiment
>      >
>      >     Seems Quantum theory has come to Raku, only we call it
>     "unboxing".
>      >
>      >
>      > As I wrote in your Raku/problem-solving issue (#154), your
>     question is
>      > not well-formed. A native value has no metadata, so how can it
>     have a
>      > type? Any experience at all with a language with pointer arithmetic
>      > should make this clear.
>      >
>      > And you issue doesn’t seem to be with unboxing—as far as I can tell,
>      > you’re unboxing (assigning to a native) just fine, it’s the
>     autoboxing
>      > that’s giving you fits.
>      >
>      > If you can show a language that can do what you want—whether it’s a
>      > `typeof` equivalent or a binary data validity checker or a magic
>     number
>      > heuristic or something else, then we may be able to help you, but
>     right
>      > now you seem to be asking for something akin to wanting to know what
>      > color the bits in your uint32 are—it’s not a question with meaning.
> 
>     Trey,
> 
>     If I ask what something is, I want an accurate answer back.
> 
> 
> What does “accurate” mean for a native value? It’s a binary blob. It has 
> no type in the memory, only in the runtime. If you successfully assigned 
> it and haven’t done any OO operations on it, as far as the runtime’s 
> concerned, it’s still the type it was when you assigned it. If you have 
> done OO operations on it, then it’s been autoboxed and you can do 
> `.^name` against it.
> 
> I’ve only asked three times, but I’ll try once more: a problem statement 
> would be helpful here.  What are you trying to achieve other than poking 
> the spot to see if it still hurts when you poke it? It may be possible 
> to do what you want with either anonymous variables or with a class 
> serving as a container for a native attribute (which can ensure that the 
> attribute can’t be autoboxed).
> 
> But just saying “I want to run this method that is undefined on this 
> thing and has no well-formed answer for this thing apart from what I can 
> see by inspecting the code” isn’t helpful in understanding what you 
> want. “And I want it to give me an *accurate* answer” doesn’t help to 
> understand what that is, either.
> 



 > my uint $u= 0xFF44; say $u.^name
Int

Wrong answer

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