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Editorial Team
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Asked: 2026-05-15T01:05:24+00:00

The standard says A variable is introduced by the declaration of an object. The

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The standard says

A variable is introduced by the declaration of an object. The variable’s name denotes the object.

But what does this definition actually mean?

Does a variable give a name to an object, i.e. are variables just a naming mechanism for otherwise anonymous objects? Or is a variable the name itself?

Or is a variable a named object in the sense that every variable is also an object?

Or is a variable just a "proxy" with a name that "delegates" all operations to the real object?

To confuse things further, many C++ books seem to treat variables and objects as synonyms.

What is your take on this?

About entities, quoting from the C++0x draft:

An entity is a value, object, reference, function […]

Every name that denotes an entity is introduced by a declaration.

A variable is introduced by the declaration of an object

From these statements I draw the conclusion that a variable is a name and thus cannot be an object. This is really confusing the hell out of me 🙂

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1 Answer

  1. Editorial Team

    Variables are named objects. The following create objects that are not variables

    new int // create one int object
std::string() // create one string object

    The following creates one array variable with name “foo” and 5 unnamed (sub-) objects of type “int”

    int foo[5];

    The following is not a variable in C++03, but has become a variable in C++0x (declared references are variables in C++0x, for details see the link)

    extern int &r;

    Does a variable give a name to an object, i.e. are variables just a naming mechanism for otherwise anonymous objects?

    Variables are objects (or references respectively). The entity list (3/3 in C++03) of C++ contains multiple such is-a relationships. For instance, a sub-object is-a object and an array element is-a object and a class-member is-a object or function or type or template or enumerator.

    The entity list of C++0x looks a bit cleaner to me, and it doesn’t contain “variables”, “instance of a function” (what that kind of entity even is has never been apparent to me), “sub-object” and “array element” anymore. Instead it added “template specialization” which either are functions, classes or templates (partial specializations).

    The C++ object model at 1.8 says

    An object can have a name (clause 3).

    So if you like, you can formulate the statement as “The object’s name denotes the object.”.

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