On 07/04/2013 03:15 AM, Joseph Rushton Wakeling wrote:
> The cast should be safe, as it's a size_t to a double.
I am commenting without fully understanding the context: Both size_t and
double are 64 bit types on a 64-bit system. double.mant_dig being 53,
converting from size_t to double loses information for many values.
import std.stdio;
import std.conv;
void main()
{
size_t i = 0x8000_0000_0000_0001;
double d0 = i.to!double;
double d1 = cast(double)i;
writefln("%s", i);
writefln("%f", d0);
writefln("%f", d1);
}
Prints
9223372036854775809
9223372036854775808.000000
9223372036854775808.000000
Still, the same information loss in a comparison may make one think that
it actually worked! :p
assert(d0 == i); // passes!
assert(d1 == i); // passes!
Ali
