Re: map allocator

"Igor Tandetnik" <>
Wed, 28 Jan 2009 07:46:26 -0500
"Mycroft Holmes" <> wrote in message

Per 23.1.8, the last argument should be an allocator whose value
type is the same as container's value type - in this case,
pair<const double, int>.

Thanks for your answer.
So in principle, should I do this?

typedef std::map<double, int, std::less<double> >::value_type
std::map<double, int, std::less<double>,

Well, I guess you could, but I don't see why you can't just write

std::map<double, int, std::less<double>,
 MYALLOCATOR<std::pair<const double, int> > m;

After all, you obviously don't feel that you have to give the third
parameter the same treatment:

typedef std::map<double, int>::key_type USUAL_KEY_TYPE;
std::map<double, int, std::less<USUAL_KEY_TYPE> > m;

What, in your opinion, makes the allocator parameter so special?
With best wishes,
    Igor Tandetnik

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