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Document number: N3793

Date: 2013-10-03

A proposal to add a utility class to represent optional objects (Revision 5)

by Fernando Cacciola, Andrzej Krzemieński

Excerpt:

Class template optional<T> proposed here is a type that may or may not store a value of type T in its storage space. Its interface allows to query if a value of type T is currently stored, and if so, to access it. The interface is based on Fernando Cacciola's Boost.Optional library, shipping since March, 2003, and widely used. It requires no changes to core language, and breaks no existing code.