Temporary Objects

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C++ Primer 7.3. The return Statement

Returning a Nonreference Type

The value returned by a function is used to initialize a temporary object created at the point at which the call was made. A temporary object is an unnamed object created by the compiler when it needs a place to store a result from evaluating an expression. C++ programmers usually use the term “temporary" as an abreviation of “temporary object."

The temporary is initialized by the value returned by a function in much the same way that parameters are initialized by their arguments. If the return type is not a reference, then the return value is copied into the temporary at the call site. The value returned when a function returns a nonreference type can be a local object or the result of evaluating an expression.