Ask basic questions for a template

broodant

Template <class _tt>
    class ……
Template <Type _tt>
    class ...
In the above two usages, the types are defined using class and Type respectively. Is there any difference?

food0012

No difference in use

firegun

I remember using class and typename, type has never been seen before

40668477

In fact, Type needs only one #define Type typename

hzxszmh

It ’s no difference, it ’s just my personal habits

lhk112

The use of class will lead to a misunderstanding. It is considered that the type used by the template is limited to the class, which is also an atomic type such as int.
typename style is better!

zfight

Agree upstairs,

These two are the same in function

zfight

Agree upstairs,

These two are the same in function

firegun

The typename has a double meaning. There is no difference between the two types of usage mentioned in the landlord, but if
template <typename C>
void print2nd (const C&container)
{
    if (container.size ()> = 2) {
        typename C :: const_iterator iter (container.begin ()); // It must be here, but only add
                                                           // typename
        ........
    }
}
The reason is that at any time you want to refer to a nested dependent type name in the template, you must put the typename immediately before it. For details, please refer to effective c ++ clause 42.

broodant

Thank you in advance.

Is it possible to specify a default value for a type specified by typename, how to do it?
is this correct
template <typename _type = string>
     class ………………
Fancy thinking, ◎ please master point ~