What's the best way to do this? I'm assuming this should be best practice:
http://dlang.org/traits.html#isSame

struct S { }
writeln(__traits(isSame, S, S));

On 4/6/15, Jonathan via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com> wrote:
> What's the best way to do this? I'm assuming this should be best
> practice:
> http://dlang.org/traits.html#isSame
>
> struct S { }
> writeln(__traits(isSame, S, S));
>

I'm not even sure when or why this trait was introduced, but you could use a simple is() expression for this, e.g.:

static if (is(T == S)) { ... }

On Mon, 06 Apr 2015 19:16:33 +0000, Jonathan wrote:

> What's the best way to do this? I'm assuming this should be best
> practice:
> http://dlang.org/traits.html#isSame
> 
> struct S { }
> writeln(__traits(isSame, S, S));


struct S {}

auto s0 = S();
auto s1 = S();

static if (is(typeof(s0) == typeof(s1))) {
  pragma(msg, "Woe to the Republic.");
}

>> static if (is(T == V))

Are static ifs always checked outside of runtime? Is it possible for a static if condition to be undeterminable outside of runtime, or would such a condition throw a compiler error?

On Tuesday, 7 April 2015 at 06:37:50 UTC, Jonathan wrote:
>>> static if (is(T == V))
>
> Are static ifs always checked outside of runtime? Is it possible for a static if condition to be undeterminable outside of runtime, or would such a condition throw a compiler error?

'static if' is always run at compile time, so it needs access to compile time information. Fortunately, you can access quite a lot at compile time in D.