[Tex/LaTex] Redefinition of \today — Clash with babel

babel

I want my calendar dates to be formatted like DD.MM.YYYY

As I am from germany I use \usepackage[ngerman]{babel}. babel breaks my redefinition of \today to use leading zeros and I don´t know why it is not possible for me to redefine it. If babel is commented out, it works fine. But defining a new command which produces the desired format is possible, see the MWE below. Can someone explain why it is not possible to redefine \today? And is it safe to redefine it or might I break some things up that rely on \today so that it would be wiser to \todayx?

MWE

\documentclass{scrbook}
\usepackage[ngerman]{babel}
\newcommand{\leadingzero}[1]{\ifnum #1<10 0\the#1\else\the#1\fi}
\renewcommand{\today}{\leadingzero{\day}.\leadingzero{\month}.\the\year}
\newcommand{\todayx}{\leadingzero{\day}.\leadingzero{\month}.\the\year}
\begin{document}
\today \\
\todayx
\end{document}

Best Answer

babel does definitions right at the start of \begin{document}, so even if \today is redefined after \usepackage{babel} this is not sufficient, but placing it in the \AtBeginDocument - hook will work. This does not require extra packages (although there nice packages such as datetime or datetime2!)

\documentclass{scrbook}
\usepackage[ngerman]{babel}

\newcommand{\leadingzero}[1]{\ifnum #1<10 0\the#1\else\the#1\fi}
\AtBeginDocument{%
\renewcommand{\today}{\leadingzero{\day}.\leadingzero{\month}.\the\year}
\newcommand{\todayx}{\leadingzero{\day}.\leadingzero{\month}.\the\year}
}
\begin{document}
\parindent=0em
\today 

\todayx
\end{document}

Related Solutions

[Tex/LaTex] getting an option clash with Babel, [english,greek]

It's because the class you're using (available here) already calls babel with the english option. The solution is to pass the greek option when loading the class file with

\documentclass[greek,<...>]{<class>}

You could also call it with a \PassOptionsToPackage{greek,english}{babel} before loading the package, therefore before \documentclass, since the class is loading it.

See:

[Tex/LaTex] \today and language (babel, xepersian)

Two things up front:

As XePersian is relying on the XeTeX engine, I would recommend using polyglossia instead of babel.
The article document class cannot use the 14pt option; for more information, take a look at this answer.

The Problem in your case is that XePersian clearly changes all western numerals (123) into genuine Arabic numerals (١٢٣), even though the XB Niloofar font contains both. Therefore, you need to tell XeTeX to use a different font than XePersian uses with \settextfont. If you do not specify a different font, XePersian will be used for typesetting, which will of course substitute the numerals.

First, of course, you need to tell XeTeX there is another language besides Farsi. You should use polyglossia to set this up: \setotherlanguage[]{english}. Then you must tell polyglossia to use a different font for all English text with \newfontfamily\englishfont{XB Niloofar}. This can of course be the exact same typeface as your XePersian \settextfont, but this time, it will not go through XePersian and thusly use the correct number forms. In the document, use \textenglish{} or \begin{english} to switch to an English environment.

Using the above suggestions will yield the following MWE:

\documentclass[12pt,a4paper]{article}

\usepackage{polyglossia}

%\setdefaultlanguage[]{farsi}
\setotherlanguage[]{english}
\newfontfamily\englishfont{XB Niloofar}

\usepackage{enumerate}
\usepackage{xepersian}

\settextfont{XB Niloofar}


\begin{document}
\today

\textenglish{\today}
\end{document}

which gives this output:

XePersian output

On a side note, setting \setdefaultlanguage[]{farsi}, which would be normal practice with polyglossia, does not work, because it clashes with XePersian, therefore it is commented out here but you are welcome to delete it.

Best Answer

Related Solutions

[Tex/LaTex] getting an option clash with Babel, [english,greek]

[Tex/LaTex] \today and language (babel, xepersian)

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