[013] template-non-type template parameters

In the template, apart from defining type parameters, we can also define non-type parameters. For example:

Temlate <unsigned N, unsigned m> int Foo (const char (& P1) [N], const char (& p2) [m]) {return strcmp (P1, p2 );}

Note that the compiler inserts an empty character at the end of a string literal constant as the final character.

For example, we call

Foo ("hi", "mom ");

In fact, the compiler will instantiate the following versions:

Int Foo (const char (P1) [3], const char (P2) [4]);

-----------

Conclusion: In the template definition, the non-type parameter of the template is a constant value. Where constant expressions are required, you can use non-type parameters, such as the size of the specified array.

[013] template-non-type template parameters