If Holder<Type> fits into POCO_SMALL_OBJECT_SIZE bytes of storage, it will be placement-new-allocated into the local buffer (i.e. there will be no heap-allocation). The local buffer size is one byte larger - [POCO_SMALL_OBJECT_SIZE + 1], additional byte value indicating where the object was allocated (0 => heap, 1 => local).
Member Functions: content
PlaceholderT * content() const;