Re: POD Class
On Feb 26, 9:40 am, Thomas Richter <t...@math.TU-Berlin.DE> wrote:
Jerry Coffin wrote:
...with one minor sort-of exception (albeit, one that doesn't apply in
this case): "For templates greater, less, greater_equal, and less_equal,
the specializations for any pointer type yield a total order, even if
the built-in operators <, >, <=, >= do not." ($20.3.3/8)
Huh, that's wierd... What's the rationale to make "greater" more
powerful than the built-in operators?
The fact that the standard associative containers use it. Back
in the days of C, the restriction was quite acceptable, because
there weren't really any (or very few) portable uses for such
comparisons anyway. For various reasons, C++ prefers to stay
compatible with C with regards to the behavior of operators, so
makes it undefined behavior as well. On the other hand, you
really don't want something like "std::set<T*>" to be undefined
behavior, and you don't want to require all of the elements to
come from a single array either.
As with many things, it's a compromize.
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