How to check if value is null, today?
tastyminerals
tastyminerals at gmail.com
Fri Oct 15 10:39:00 UTC 2021
On Thursday, 14 October 2021 at 12:43:36 UTC, jfondren wrote:
> On Thursday, 14 October 2021 at 11:58:29 UTC, tastyminerals
> wrote:
>> Here is an example code that doesn't work with the new
>> compiler anymore:
>>
>> ```
>> if (someValue.isNull)
>> ```
>>
>> Attempting to run the above throws:
>> ```
>> Error: incompatible types for `(0) : (someValue)`: `int` and
>> `Nullable!int`
>> ```
>>
>
> Do you have a complete example? Because this runs without error:
>
> ```d
> import std.typecons : nullable, Nullable;
> import std.stdio : writeln;
>
> void main() {
> auto a = nullable(1);
> auto b = Nullable!int.init;
> if (!a.isNull)
> writeln(a.get);
> if (b.isNull)
> writeln("b is null");
> }
> ```
Steven Schveighoffer was correct, the error was caused by non
explicit `someVar;` which had to be changed to `someVar.get;`.
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