The core of the system

The problems described in sections  and  can be solved using the babel system of document-style options.

The core of this system currently performs three functions.

1. It defines a user interface for switching between languages;

2. It contains code to dynamically load several sets of hyphenation patterns;

3. It `repairs' the document styles provided in the standard distribution of L^ATEX.

Obviously part  can only be used while running iniTEX to create a new format, whereas part  should not be read by iniTEX. Part  should even disappear when L^ATEX version 3.0 arrives, as the style files supplied with the new L^ATEX will no longer be language specific. Part  can either be loaded into the format with multiple hyphenation patterns, or it can be read while processing a document.

For this reason the core of the babel system is stored in two separate files, babel.switch, containing parts  and , and babel.sty which contains part . The file babel.sty will instruct L^ATEX to load babel.switch if necessary, the file babel.switch checks the format to see if hyphenation patterns can be loaded.