the enclosing type to introspect.
      </p>
<p>
        The metafunction returns a single type called 'type', which is a boost::mpl::bool_.
        As a convenience the metafunction returns the value of this type directly
        as a compile time bool constant called 'value'. This is true or false depending
        on whether the inner class template exists or not.
      </p>
</div>
</div>
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