HP Integrity NonStop H-Series - Manual (Page 220)

matrix > long_matrix;
Of course you don't even have to specialize on matrix_traits. You just have to make sure you
provide the interface that matrix expects from its traits template parameter.
Most of the time, the operations contained in a traits class will be static functions so that there's
no need to actually instantiate a traits object.
The Standard Library uses this technique to give the string class maximum flexibility and
efficiency across a wide range of types. The string traits class provides elementary operations
on character arrays. In the simplest case, this means providing string a wstring with access to
the 'C' library functions for skinny and wide characters, for example Strcpy and wcstrcpy.
See the string_char_traits reference entry for a complete description of the traits class.