`\\' doesn't work in @math

[Werner LEMBERG]

In previous versions (before 4.1), the following worked:

  Default: @address@hidden * 5 / 6}.

Now this fails.  Sigh.  Doing this:

  Default: @math{\code{\\n[LL]} * 5 / 6}.

fails also:

  ! Argument of \\ has an extra }.
  <inserted text>
                  \par
  <to be read again>
                     }
  \tclose ...nation \rawbackslash \frenchspacing #1}
                                                    \null
  \codex #1->\tclose {#1}
                         \endgroup
  <argument> \code {\\n[LL]}
                             * 5 / 6
  \finishmath #1->#1
                    \implicitmath \Etex
  l.2710 Default: @math{\code{\\n[LL]} * 5 / 6}

This means that the transition `@'->`\' resp. the doubling of the
backslash doesn't work in general.  Resorting to `\rawbackslashxx' is
not funny.


    Werner