Operator overloading or alternatives to expression templates

[Andrei Alexandrescu via Digitalmars-d]

On 09/13/2015 01:16 PM, Daniel N wrote:
> On Sunday, 13 September 2015 at 14:06:46 UTC, Martin Nowak wrote:
>>   struct Foo
>>   {
>>       size_t id;
>>       int opCmp(Foo rhs)
>>       {
>>           if (id < rhs.id) return -1;
>>           if (id == rhs.id) return 0;
>>           else return 1;
>>       }
>>       bool opBinary(string s:"<")(Foo rhs)
>>       {
>>           return id < rhs.id;
>>       }
>>   }
>>
>>   Sorting a million Foos w/ random ids is 37.5% slower with opCmp.
>>
>
> Could you try this?
>
> int opCmp(Foo rhs)
> {
>    return (id > rhs.id) - (id < rhs.id);
> }

Apparently that does well with gcc: 
http://stackoverflow.com/questions/10996418/efficient-integer-compare-function 
-- Andrei