export (thing)

export is a little-known keyword listed in the ANSI standard for the C++ programming language. Rarely (if ever!) implemented by compiler writers, the purpose of export is to allow templated class definitions to be compiled to an intermediate form so that they can be reused between projects, included in multiple compilation units, or given to strangers (possibly in exchange for candy) without the need to include the entire templated class declaration and recompile it every time it's used. An example of its usage:

export template<typename T> class Foo
{
    T value;

public:
    Foo(T initValue)
        {value = initValue;}

    T negate()
        {return -value;}
};

Most compilers recognize the keyword, but treat it as a no-op. To date, only two compilers even pretend to support the keyword: Comeau C++ and Edison C++. The Edison Design Group (creators of Edison C++) license compilers to Microsoft, so it's always possible that support for export will eventually make its way into Microsoft's development suite, and thus into widespread usage. With Microsoft's increasing focus on .NET, however, this is unlikely.