Fix std.format FP printing for soft-float targets

[kinke]

After #7362.

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[ghost]

Instead of importing std.math completely, wouldn't it be better to have something like enum hasFloatingPointControlSupport in std.math import this and in case of it being true doing import std.math : FloatingPointControl?

[kinke]

The local import only affects the little then branch of the if...

[ghost]

That "little then branch" will grow with PRs #7264 and #7318 and the followups and eventually end in being the whole template. Anyway, it's still local of course and I personally would not mind. But as far as I know, we are currently trying to reduce the imports as much as possible, don't we? I think, some modules are even checked for whole imports by the style checker and would be rejected...

[kinke]

AFAIK, the only difference for a whole import here is the namespace pollution, but as long as that's restricted to a little then (or in the future, possibly its own little getRoundingMode()), I see no problem with it, and would find a

import std.math : isFloatingPointControlAvailable;
static if (isFloatingPointControlAvailable)
{
    import std.math : FloatingPointControl;
    ...
}

much uglier.

[ghost]

For me both is fine.

[n8sh]

std/format.d(2661:20)[warn]: Local imports should specify the symbols being imported to avoid hiding local symbols.

Yeah maybe this wasn't a good rule since it defeats this kind of compile time introspection.

[wilzbach]

Yeah maybe this wasn't a good rule since it defeats this kind of compile time introspection.

The rules can be selectively disabled in .dscanner.ini

[kinke]

Does the bot ignore the 72h... label?

[wilzbach]

Yes, the label is just for humans.