Read Once then reset/init value?

[Robert M. Münch]

On 2019-10-29 23:28:35 +0000, Simen Kjærås said:

> On Tuesday, 29 October 2019 at 22:24:20 UTC, Robert M. Münch wrote:
>> I quite often have the pattern where a value should be read just once 
>> and after this reset itself. The idea is to avoid that others read the 
>> value by accident and get an older state, instead they get an 
>> "invalid/reset" value.
>> 
>> Is there a library function that can mimic such a behaviour?
> 
> Something like this?
> 
> T readOnce(T)(ref T value) {
>      auto tmp = value;
>      value = T.init;
>      return tmp;
> } unittest {
>      int i = 3;
>      assert(i.readOnce == 3);
>      assert(i == 0);
> }
> 
> If so, no, there is no library function for it, but feel free to use 
> the above. You may very well have to change T.init to something more 
> fitting for your use case, of course.

Hi, that looks very good. I forgot about the UFCS possibility. That's 
very good because it works on basic types too. Thanks :-)

-- 
Robert M. Münch
http://www.saphirion.com
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