What is the Purpose and Evolution of the Injected Class Name in C ?

Deciphering the Injected Class Name: Its Purpose and Evolution in C

Introduction:
The concept of an injected class name in C has puzzled many programmers. This feature allows a class to become a member of itself, enabling unambiguous name resolution within the class body.

Purpose of the Injected Class Name:
The injected class name ensures that within the scope of a class, its own name always refers to the current class rather than another class with the same name declared in the same enclosing scope. This distinction is crucial in scenarios like class methods that might refer to either the method or a temporary object of the same name.

Clarification in C 03:
While the idea of an injected class name existed in C 98, its terminology was introduced in C 03 with the publication of the [class]/2 section in the C standard. This section explicitly states that a class name is injected into both the scope of its declaration and the scope of the class itself.

Benefits within Class Templates:
The injected class name is particularly useful in class templates. It allows the template parameter list to be omitted when referring to the current instantiation of the class, making usage more straightforward.

Historical Background:
Even prior to C 98, the ARM (Annotated Reference Manual) included provisions that allowed a class' name to be utilized within its own member list. This concept laid the groundwork for the formalization of the injected class name in subsequent C versions.

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