In order to use any function with this object, we need to write the object name, a dot, and the name of the function.
And the compiler basically only needs a definition to produce an instance of that class, object, struct, variable, etc. A class declaration in C++ is frequently also a definition or partial definition. Here is a detailed description of the differences on stack overflow.
Class definition and declaration in C++. Classes can be defined by using the keyword "class" and the class name. Access modifiers, data variables, and member functions are present inside this class. Now, fully comprehend them.
A forward declaration of a class might look like this: This only informs the compiler of the existence of that class; it makes no mention of its members, base classes, or other details.
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