Non-type template parameters (for C ++)

The parameter format of the non-type template is the same as that of the following type.

• Integer or enumeration
• Point to an object or function
• Reference to an object or function
• Point to a member

Declare non-type template parameters as an array or function, and convert them into pointers and pointers to functions. The following example demonstrates the following:

1 template <int a [4]> struct {};
2 template <int f (int)> struct B {};
3
4 int I;
5 int g (int) {return 0 ;}
6
7 A <& I> x;
8 B <& g> y;

Type & I is derived from int *, and type & g is derived from int (*) (int ).

You can use const or volatile to modify non-type template parameters.

You cannot declare a non-type template parameter as a float pointer, class, or void type.

The parameter of the non-type template is not the left value.

Reference: IBM