Format

[cc]

On Saturday, 22 May 2021 at 03:14:35 UTC, cc wrote:
> Oops, disregard this.  I had an error in my imports.😓
> It does in fact work in @safe.

I should add as an aside then that there is an issue of errors 
from the body of a toString template not being displayed, and 
instead the template being silently skipped, e.g.:

```d
@safe void toString(W)(ref W writer) if (isOutputRange!(W, char)) 
{
	writer.formattedWrite("FOO:%s", x);
	syntactically correct; // Program will compile without error, 
but this function will now never be called
}
```

I ran into a similar challenge with opDispatch some time ago: 
https://forum.dlang.org/post/axgwhzzawncbpcvqqrur@forum.dlang.org
In this case I assume it's some consequence of NOT wanting to 
emit a warning or error for every single class or struct that 
doesn't have a templated toString when the various output writers 
go looking for one.

Something like this can help reveal errors, not sure if there's 
an easier way:
```d
unittest {
	struct DebugWriter {
		void put(C)(C c) {}
	}
	DebugWriter wr;
	Foo foo;
	foo.toString(wr);
}
```
`Error: undefined identifier 'syntactically'`
`Error: template instance 
'amemfailuretest.Foo.toString!(DebugWriter)' error instantiating`