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In-Reply-To: <E7FAB304-98EB-45E5-95D1-6E44AD78C68A@benramsey.com>
Date: Thu, 7 Dec 2023 20:26:30 +0900
Message-ID: <CAOyH9yTAHGHTXjx03OXSCpRpU38hf0W0+ZV9-L=71o5hsvBrcw@mail.gmail.com>
To: Ben Ramsey <ben@benramsey.com>
Cc: PHP Developers Mailing List <internals@lists.php.net>
Content-Type: multipart/alternative; boundary="000000000000f625a4060be9bdf7"
Subject: Re: [PHP-DEV] Proposal: Arbitrary precision native scalar type
From: alex.pravdin@interi.co (Alexander Pravdin)

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>
> Someone tangential to your proposal, have you given any thought to
> implementing this similar to how Python treats numbers?
>

Unfortunately, I don't know many details of numbers treatment in Python...


In Python, integers have unlimited precision. I=E2=80=99m not sure how they=
 store
> the values internally, but to users of Python, any sequence of numbers is
> an `int`, no matter how long it is.
>
> For example, this multiplies the max 64-bit, signed integer by 2, and the
> result is still an `int`:
>
>     >>> i =3D 9223372036854775807 * 2
>     >>> i
>     18446744073709551614
>     >>> type(i)
>     <class 'int=E2=80=99>
>
> And this is a really, really, really long number that=E2=80=99s still an =
`int`:
>
>     >>> x =3D
> 9223372036854775807922337203685477580792233720368547758079223372036854775=
807
>     >>> x
>
> 9223372036854775807922337203685477580792233720368547758079223372036854775=
807
>     >>> type(x)
>     <class 'int=E2=80=99>
>

I'm not sure about integers, I mostly care about decimals :) Decimals can
hold big rounded ints as well. The limit on the maximum number here will be
the underlying library's limit.


However, if we can achieve arbitrary-length integers, is there a reason we
> couldn=E2=80=99t also have arbitrary length floating point numbers?
>

I'm not familiar with arbitrary-length integers so I don't know what to say
here...



> Below a certain threshold, we could use the system=E2=80=99s native int a=
nd double
> for storage and math. Above a certain threshold, we could internally swit=
ch
> to a bundled library for handling arbitrary-precision integers and floats=
,
> and it would be seamless to the user, who would see only `int` and `float=
`
> types in PHP.
>

I guess this could be a topic of the next step discussion after "decimal"
introduction.


Anyway, this is something I=E2=80=99ve been thinking about for some time, b=
ut I
> haven=E2=80=99t taken the time to look into what it might take to impleme=
nt it. It
> sounds like you have looked into it, so I=E2=80=99m interested to know wh=
ether you
> think what I=E2=80=99ve described here is feasible.
>

I was only thinking about decimals and I'm not an expert in low-level
manipulation of numbers.



Best regards,
Alex.

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