how to test (at compilation-time) for existence of an already-declared object ?

someone someone at somewhere.com
Sat Jul 24 01:55:44 UTC 2021


On Saturday, 24 July 2021 at 01:44:11 UTC, Adam D Ruppe wrote:
> On Saturday, 24 July 2021 at 01:29:26 UTC, someone wrote:
>> Suppose I have a module with the following:
>
>
> static if(is(classTickerCustomNYSE))
>    // it was a valid type
> else
>   // it was not a valid type
>
>
> can use that to test. you can also mix in the name
>
>
> static if(is(mixin("class name here"))) {}
>
>
>
> There's similar tricks for testing for imports and such too but 
> i recommend here you import the module first then can test it.

is() ... faaan-tas-tic :)

I completely forgot about the is operator and went looking all 
over the place for something like that.

Man ... leaving templates aside for a moment, conditional 
compilation alongside mixin is pretty powerful in D ! I can't 
believe how flexible code I am writing right now; and I am only a 
beginner ...

Thanks for the tip Adam !


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