<\body> <\explain> <|explain> If is a string, the length of the string is returned. For instance, > evaluates to . <\explain> <|explain> Return the substring of starting at position and ending at position (not included). For instance, > evaluates to . <\explain> >|expr-n> <|explain> This primitive may be used to concatenate several strings until . For instance, > produces . <\explain> <|explain> Renders a in a specified way. Supported values for are <\description> Lower case Roman: > > . Upper case Roman: > > . Lower case letters: > > . Upper case letters: > > . Arabic numbers: > > . Footnotes symbols: > > . <\explain> <|explain> Returns the current date in a specified (which defaults to a standard language-specific format when empty) and a specified (which defaults to English). The format is similar to the one used by the command. For instance, > evaluates to ``'', > to ``'' and > to ``''. <\explain> <|explain> Returns the translation of a string of the language into the language , using the built-in dictionaries. The languages should be specified in lowercase letters. For instance, > yields ``''. The list of currently available languages can be checked in the menu. The built-in dictionaries can be found in When attempting to use a non-existing dictionary, the program may quit. For most purposes, it is more convenient to use the macro, which converts a string from English into the current language.