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Date: Sat, 28 Oct 2023 16:33:04 +0100
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Subject: Re: [PHP-DEV] New DateTime[Immutable]::createFromTimestamp
From: rowan.collins@gmail.com (Rowan Tommins)

On 28 October 2023 15:40:29 BST, Saki Takamachi <saki@sakiot=2Ecom> wrote:
>Hi Marc,
>
>Personally, I don't think these are necessarily necessary since there is =
a "from format"=2E

As noted on the PR, both the default constructor and createFromFormat requ=
ire the input to be converted to a string, which tends to make code messy=
=2E It's then converted back to an integer internally, which isn't very eff=
icient=2E

I would be in favour of adding this method=2E


>I have one concern=2E float is imprecise, so I don't think it's suitable =
for this kind of use=2E For timestamps, 16 digits are used, which exceeds t=
he guaranteed precision of 15 digits on non-IBM platforms=2E

I'm not sure where you got those numbers; on a 64-bit architecture (surely=
 the vast majority of PHP installs), a float can precisely represent any wh=
ole number from -2**53 up to 2**53 - 1=2E As a Unix timestamp, that's a one=
-second accuracy for any time 285 million years into the past or future=2E =
https://www=2Ewolframalpha=2Ecom/input?i=3D2**53+as+unix+timestamp

Possibly you're thinking of a representation that counts integers as milli=
seconds or microseconds, instead of seconds?

Regards,

--=20
Rowan Tommins
[IMSoP]