Display materialization, display instantiation, implicit instantiation

To discuss the differences between the three, we need to know the function template first, the function template is a new addition to C + +, and he creates a generic function to support a variety of different types of parameters, avoiding the repetitive design of the function body, when we need to reuse a piece of code but need to handle different types of arguments, Using a function template is a convenient means his biggest feature is the data type also as a parameter. Each function uses a function template to allow several functions to use a common template parameter, and you should use a template class

Display instantiation:

Template  void  swap<int> (int, int);

Show Materialization: (define job as a struct)

Template <> void swap<job> (Job &,job &);

       or     template<>  void Swap   (Job &,job &);

We can see from the definition form that the difference is that the former begins with template and the latter begins with template<>.
In terms of meaning, display materialization tells the compiler not to use the function template of swap () to generate a function definition, while using a specialized job type to explicitly define a function definition is to provide a materialized function definition that includes the required code, and when the compiler finds the materialized definition that matches the function call, The definition is used instead of looking for a template, and display instantiation generates an instance function that indicates a particular parameter type

To sum up:
Implicit instantiation : Before using a template, the compiler does not generate the declaration and definition examples of the template, and the compiler will generate an instance function based on the template.
explicit instantiation : Is the compiler generates an instance function whether or not there is a program
display materialization : Because for some special types, it may not be suitable for the template implementation, you need to redefine the implementation, this time using the scene that shows materialization