LaTeX versus Html mode Contents Index

## LaTeX versus Html mode

The easiest way to put a command or text in your document that is only included in one of the two output modes it by using a \texonly or \htmlonly command. They ignore their argument, if in the wrong mode, and otherwise simply expand it:

We are now in \texonly{\LaTeX}\htmlonly{HTML}-mode.

In cases such as this you can simplify the notation by using the \texorhtml command, which has two arguments:

We are now in \texorhtml{\LaTeX}{HTML}-mode.

Another possibility is by prefixing a line with \T or \W. \T acts like a comment in HTML-mode, and as a noop in LaTeX-mode, and for \W it is the other way round:

We are now in
\T \LaTeX-mode.
\W HTML-mode.

The last way of achieving this effect is useful when there are large chunks of text that you want to skip in one mode--a HTML-document might skip a section with a detailed mathematical analysis, a LaTeX-document will not contain a node with lots of hyperlinks to other documents. This can be done using the iftex and ifhtml environments:

We are now in
\begin{iftex}
\LaTeX-mode.
\end{iftex}
\begin{ifhtml}
HTML-mode.
\end{ifhtml}

In LaTeX, commands that are defined inside an enviroment are "forgotten" at the end of the environment. So LaTeX commands defined inside a iftex environment are defined, but then immediately forgotten by LaTeX. A simple trick to avoid this problem is to use the following idiom:

\W\begin{iftex}
... command definitions
\W\end{iftex}

Now the command definitions are correctly made in the Latex, but not in the Html version.

Instead of the iftex environment, you can also use the tex environment. It is different from iftex only if you have used \NotSpecial in the preamble.

The environment latexonly has been provided as a service to latex2html users. Its effect is the same as iftex.

Tom Sgouros, September 13, 2005

 LaTeX versus Html mode Contents Index