what's the difference between
template<typename T>
auto add1(const T& a, const T& b)
{ return a + b; }
and
template<typename T>
auto add2(T a, const T& b)
{ return a += b; }
?
if you know the answer you are better than boost
🇳🇱
@namark Are you asking because you dont know, or as a riddle?
@freemo Not entirely sure about performance characteristics myself, good hunch that the differences are minor, but as far as I know add2 can actually be faster in some cases, if you take optimizations in consideration, and the reason it could be slower is not at all what you suggest, it usually is about construction and copying of objects.
There is a notable functional difference though, but not gonna hint too hard for now.
@namark id be curious to see benchmarks on it to suggest the differences. But yea i cant be 100% on the performance here, instinct tells me 2 is slower, but compiler magic can do all sorts of stuff I dont anticipate.
@namark well my C++ is a little rusty but functionally they should be relatively equivalent as far as I can tell. The second one may be a bit slower as it reassigns a variable with function level scope before returning it (and the scope therefore being dropped)... but aside from the second one being a little inefficient they should behave the same.