Re: [boost] Please don't define a fake "operator <" justfor orderedcontainers

From: Martin Bonner (martin.bonner_at_[hidden])
Date: 2006-07-11 06:33:52

----Original Message----
From: boost-bounces_at_[hidden]
[mailto:boost-bounces_at_[hidden]] On Behalf Of Peter Dimov Sent:
11 July 2006 11:18 To: boost_at_[hidden]
Subject: Re: [boost] Please don't define a fake "operator <" justfor
orderedcontainers 

> 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.
> 
> "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.  Now admittedly, operator <() for std::string doesn't actually correspond to my natural ordering (Zoë should be less than Zoo, but it isn't), but it is close enough for most purposes and much cheaper than a locale sensitive comparison.

-- 
Martin Bonner
Martin.Bonner_at_[hidden]
Pi Technology, Milton Hall, Ely Road, Milton, Cambridge, CB4 6WZ,
ENGLAND Tel: [phone]