Martin Bonner wrote:
----Original Message---- From: boost-bounces@lists.boost.org [mailto:boost-bounces@lists.boost.org] On Behalf Of Peter Dimov
Daryle Walker wrote:
[1] If you make a fake order for "std::complex<>", would you compare real components then imaginary components, or would you use magnitude then angle?
Real, then imaginary. Compare with:
Interesting. I would have chosen magnitude and then angle. Why components.
There are two reasons for that. First, composite types use lexicographical ordering by default, and std::complex is (de facto) a (real, imag) pair. Second, the magnitude/angle ordering has the property that if you have three numbers a, b, c, where a and b are very close to one another but not to c, it is possible to have a < c and c < b.
"If you make a FAKE order for std::string, would you compare left to right or right to left?"
I don't think that is a legitimate comparison. In my world view, strings have a natural order but complex numbers don't.
Possibly. So you define "fake" as "unnatural", and define "natural" as "feels natural to me". This approach can work but it's a bit subjective, isn't it? Consider the progression: complex<double> struct { double x, double y; } pair<double, double> tuple<double, double> vector<double> vector<char> string If we take the "feel" of operator< out of the equation, where should we draw the line, and based on what?