Re: printing template argument

On May 8, 9:27 pm, Venkat <swara...@[EMAIL PROTECTED]
> wrote:
> > std::cout << typeid(C).name() << std::endl;
>
> Doesn't it incur runtime cost?
> I'm wondering something that would be resolved at compile time.

Only if used on a polymorphic lvalue. Otherwise, a decent compiler can
and should optimize to produce the type_info for the static type of
the object. Since you are always using a type, and not a value, you
won't suffer any cost.

> While typeid(C).name() is guaranteed to be unique for each class C,
> it is NOT guaranteed to be anything human-understandable.  This
> makes the function rather useless, but that's what the standard says.

Unfortunately, not even. The result of type_info.name() is
unspecified, and no requirements are put onto it. "" is a perfectly
valid value of type_info.name() for any and all types.

Sean Hunt


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