A large part of the core of the babel system is dedicated to `repair' the standard document styles. This means redefining the macros in table .
As an example of the way the macros have to be redefined, the
redefinition of \tableofcontents
is shown in figure .
The standard styles can be distinguished by checking the existence of the
macros \chapter
(not in article and letter) and
\opening
(only in letter). The result of these checks is stored in
the macro \doc@style
. When \doc@style
already exists (which is
the case when for instance artikel1.sty is used [7]) it is not
superseded (see figure ).