Hi,

Is there a way for a templated function to deduce or apply the @safe/@nogc attributes automaticaly? I feel like I remember dmd doing so at one point, but it doesn't appear to work anymore. In particular, I need to call a function belonging to a templated type, but do not know what attributes are applied.

eg.

void func(T)(T t)
{
    //Don't know if safe or nogc
    t.someFunc();
}

Thanks.

On Saturday, 18 November 2017 at 17:28:14 UTC, David  Zhang wrote:
> Hi,
>
> Is there a way for a templated function to deduce or apply the @safe/@nogc attributes automaticaly? I feel like I remember dmd doing so at one point, but it doesn't appear to work anymore. In particular, I need to call a function belonging to a templated type, but do not know what attributes are applied.
>
> eg.
>
> void func(T)(T t)
> {
>     //Don't know if safe or nogc
>     t.someFunc();
> }
>
> Thanks.

If you instantiate  "func" the compiler should correctly infer the attributes. Do you have any code where it doesn't work?

On Saturday, November 18, 2017 17:28:14 David Zhang via Digitalmars-d-learn wrote:
> Hi,
>
> Is there a way for a templated function to deduce or apply the @safe/@nogc attributes automaticaly? I feel like I remember dmd doing so at one point, but it doesn't appear to work anymore. In particular, I need to call a function belonging to a templated type, but do not know what attributes are applied.
>
> eg.
>
> void func(T)(T t)
> {
>      //Don't know if safe or nogc
>      t.someFunc();
> }
>
> Thanks.

pure, nothrow, @safe, and @nogc are infered for templated functions. So, whether those attributes apply when they're not explicitly marked on a templated function deponds on the contents of the function. You can test it with a unit test. e.g.

@nogc unittest
{
    ...
    foo.func();
}

will give a compiler error if func wasn't infered as @nogc.

- Jonathan M Davis

Huh, I think I did something weird. It compiles now, and I don't know why. Thanks for your answers.