### Compilation Errors Indicating that an Element Type or Function Is Not Declared

#### Effect

You get compiler messages when processing templates indicating that an element type or one of its required element functions is not declared.

#### Reason

The element type or element function is defined locally to the source file that contains the template instantiation with the element type as its argument. The prelink or prebind phase is executed only by using the header files. Therefore, your declaration local to a source file is not recognized and causes these compilation errors.

#### Solution

Move the corresponding declarations to a separate header file and include the header file from the source file.

Introduction to the Collection Classes
Overall Implementation Structure
Element Functions and Key-Type Functions

Implementing Element- and Key-Type Functionality
Defining Member Functions of the Element Object Type
Defining Separate Global Functions
Using or Defining an Element Operation Class
Memory Management with Element Operation Classes
Possible Implementation Paths
Choosing One of the Provided Implementation Variants
Instantiating the Collection Classes