Re: [PATCH 2/5] rust: time: Introduce Duration type

[Benno Lossin]

On 26.03.24 18:17, Boqun Feng wrote:
> On Tue, Mar 26, 2024 at 10:11:07AM -0700, Boqun Feng wrote:
> [...]
>>>> +impl Duration {
>>>> +    /// Creates a new duration of `ns` nanoseconds.
>>>> +    pub const fn new(ns: i64) -> Self {
>>>> +        Self { inner: ns }
>>>> +    }
>>>> +
>>>> +    /// Divides the number of nanoseconds by a compile-time constant.
>>>> +    #[inline]
>>>> +    fn divns_constant<const DIV: i64>(self) -> i64 {
>>>> +        self.to_ns() / DIV
>>>> +    }
>>>
>>> I am a bit confused, why is this better than writing
>>> `self.to_ns() / DIV` at the callsite?
>>>
>>
>> Hmm.. you're right, there should be no difference I think. If there is
>> nothing I'm missing from Alice, I will drop this function in the next
>> version.
>>
> 
> On a second thought, I think this prevents accidentally divide a
> non-const value, in other words, if you use this function, you're
> guaranteed the divisor is a constant, and you have the compiler checking
> that for you. So in that sense, I think it makes sense to remain it
> here. Thoughts?

I don't see the value in that. It does not prevent me from just doing
`self.to_ns() / DIV` now. I imagine that 99% of the time users will want
to get milliseconds or microseconds and we should have methods for that
(when we have users). But for the last 1% I don't think we need this
method.

-- 
Cheers,
Benno