On Wednesday, 17 May 2023 at 08:00:17 UTC, Dom DiSc wrote:
If you want auto-conversion, you should be more explicit:
```d
float opCast() { }
```
because if you return "auto" it is not the highest-prio fit and
therefore not chosen.
If you have multiple choices, you still don't need to use
"auto". Instead you can return T:
```d
T opCast(T)() if(isFloatingPoint!T)
{
return cast(T)num / cast(T)den; // float, double or real
}
```
Kind of ironic, but especially "auto" does NOT fit
automatically :-)
Sorry for not expressing myself better. Let me try to explain
with another example:
```d
struct RightShift
{
int num, shr;
T opCast(T : char)()
=> cast(T)(num >> shr);
}
import std.stdio;
void main()
{
auto f = RightShift(128, 2);
char chr = cast(char)f | '\1';
assert(chr == '!');
//char test = f; // Error: cannot implicitly convert expression
//assert(test == ' '); // `f` of type `RightShift` to `char`
}
```
This snippet works fine. But hidden the code gives an error.
The reason is that the compiler ignores the explicitly specified
lines without using auto.
SDB@79
