C + + generic programming and template learning

Generic programming, English called Generic programming

Can be understood as, universal meaning, universality, programming.

For example, you would implement a function to compare the size of two numeric values, which could be either int or string. For the first attempt, we intuitively think of defining multiple overloaded functions. As follows:

int compare (const string &V1, const string &v2)

{

if (V1 < v2) return-1;

if (V2 < v1) return 1;

return 0;

}

int compare (const int &V1, const int &V2)

{

if (V1 < v2) return-1;

if (V2 < v1) return 1;

return 0;

}

These two functions are almost identical except for the type of the parameter. As the types of comparisons increase, we have to define a number of similar and redundant functions.

Generic programming is designed to solve such problems, so that we can write code independently of any particular type.

Templates are the basis for C + + generic programming. The template definition starts with the keyword template followed by a list of templates parameters. The template parameter list is surrounded by <> with one or more template parameters separated by commas.

For example, the above requirements can be written as follows:

Template <typename t>

int compare (const t &V1, const T &V2)

{

if (V1 < v2) return-1;

if (V2 < v1) return 1;

return 0;

}

C + + generic programming and template learning