Moving information aroundTopConditional CompilationCarrying onContentsIndex

Carrying on

In this section we continue to Chapter 3 of the LaTeX-book, dealing with more advanced topics.

Changing the type style

Hyperlatex understands the following physical font specifications of LaTeX2e: In LaTeX2e font changes are cumulative--\textbf{\textit{BoldItalic}} typesets the text in a bold italic font. Different HTML browsers will display different things.

The following old-style commands are also supported:

So you can write
  {\it italic text}
but also
  \textit{italic text}
You can use \/ to separate slanted and non-slanted fonts (it will be ignored in the HTML-version).

Hyperlatex complains about any other LaTeX commands for font changes, in accordance with its general philosophy. If you do believe that, say, \sf should simply be ignored, you can easily ask for that in the preamble by defining:

  \W\newcommand{\sf}{}

Both LaTeX and HTML encourage you to express yourself in terms of logical concepts instead of visual concepts. (Otherwise, you wouldn't be using Hyperlatex but some WYSIWYG editor to create HTML.) In fact, HTML defines tags for logical markup, whose rendering is completely left to the user agent (HTML client).

The Hyperlatex package defines a standard representation for these logical tags in LaTeX--you can easily redefine them if you don't like the standard setting.

The logical font specifications are:

Changing type size

Hyperlatex understands the LaTeX declarations to change the type size. The HTML font changes are relative to the HTML node's basefont size. (\normalfont being the basefont size, \large begin the basefont size plus one etc.)

Symbols from other languages

Hyperlatex recognizes all of LaTeX's commands for making accents. However, only few of these are are available in HTML. Hyperlatex will make a HTML-entity for the accents in ISO Latin 1, but will reject all other accent sequences. The command \c can be used to put a cedilla on a letter `c' (either case), but on no other letter. So the following is legal
     Der K{\"o}nig sa\ss{} am wei{\ss}en Strand von Cura\c{c}ao und
     nippte an einer Pi\~{n}a Colada \ldots
and produces

Der König saß am weißen Strand von Curaçao und nippte an einer Piña Colada ...

Not available in HTML are Ji{\v r}\'{\i}, or Erd\H{o}s. (You can tell Hyperlatex to simply typeset all these letters without the accent by using the following in the preamble:
   \newcommand{\HlxIllegalAccent}[2]{#2}

Hyperlatex also understands the following symbols:

oe \oe å \aa ¿ ?`
OE \OE Å \AA ¡ !`
æ \ae ø \o ß \ss
Æ \AE Ø \O
§ \S © \copyright
\P £ \pounds

\quad and \qquad produce some empty space.

Defining commands and environments

Hyperlatex understands definitions of new commands with the LaTeX-instructions \newcommand and \newenvironment. \renewcommand and \renewenvironment are understood as well (Hyperlatex makes no attempt to test whether a command is actually already defined or not.) The optional parameter of LaTeX2e is also implemented.

 

If you use \providecommand, Hyperlatex checks whether the command is already defined. The command is ignored if the command already exists.

Note that it is not possible to redefine a Hyperlatex command that is hard-coded in Emacs lisp inside the Hyperlatex converter. So you could redefine the command \cite or the verse environment, but you cannot redefine \T. (But you can redefine most of the commands understood by Hyperlatex, namely all the ones defined in siteinit.hlx.)

Some basic examples:

   \newcommand{\Html}{\textsc{Html}}

   \T\newcommand{\bad}{$\surd$}
   \W\newcommand{\bad}{\htmlimg{badexample_bitmap.xbm}{BAD}}

   \newenvironment{badexample}{\begin{description}
     \item[\bad]}{\end{description}}

   \newenvironment{smallexample}{\begingroup\small
               \begin{example}}{\end{example}\endgroup}

Command definitions made by Hyperlatex are global, their scope is not restricted to the enclosing environment. If you need to restrict their scope, use the \begingroup and \endgroup commands to create a scope (in Hyperlatex, this scope is completely independent of the LaTeX-environment scoping).

Note that Hyperlatex does not tokenize its input the way TeX does. To evaluate a macro, Hyperlatex simply inserts the expansion string, replaces occurrences of #1 to #9 by the arguments, strips one # from strings of at least two #'s, and then reevaluates the whole. Problems may occur when you try to use %, \T, or \W in the expansion string. Better don't do that.

Theorems and such

The \newtheorem command declares a new "theorem-like" environment. The optional arguments are allowed as well (but ignored unless you customize the appearance of the environment to use Hyperlatex's counters).
   \newtheorem{guess}[theorem]{Conjecture}[chapter]

Figures and other floating bodies

You can use figure and table environments and the \caption command. They will not float, but will simply appear at the given position in the text. No special space is left around them, so put a center environment in a figure. The table environment is mainly used with the tabular environment. You can use the \caption command to place a caption. The starred versions table* and figure* are supported as well.

Lining it up in columns

The tabular environment is available in Hyperlatex.

Many column types are now supported, and even \newcolumntype is available. The | column type specifier is silently ignored. You can force borders around your table (and every single cell) by using \xmlattributes*{table}{border} immediately before your tabular environment. You can use the \multicolumn command. \hline is understood and ignored.

The \htmlcaption has to be used right after the \begin{tabular}. It sets the caption for the HTML table. (In HTML, the caption is part of the tabular environment. However, you can as well use \caption outside the environment.)

If you have made the & character non-special, you can use the macro \htmltab as a replacement.

Here is an example:

    \begin{table}[htp]
    \T\caption{Keyboard shortcuts for \textit{Ipe}}
    \begin{center}
    \begin{tabular}{|l|lll|}
    \htmlcaption{Keyboard shortcuts for \textit{Ipe}}
    \hline
                & Left Mouse      & Middle Mouse  & Right Mouse      \\
    \hline
    Plain       & (start drawing) & move          & select           \\
    Shift       & scale           & pan           & select more      \\
    Ctrl        & stretch         & rotate        & select type      \\
    Shift+Ctrl  &                 &               & select more type \T\\
    \hline
    \end{tabular}
    \end{center}
    \end{table}
The example is typeset as follows:

Keyboard shortcuts for Ipe
Left Mouse Middle Mouse Right Mouse
Plain (start drawing) move select
Shift scale pan select more
Ctrl stretch rotate select type
Shift+Ctrl select more type

Note that the netscape browser treats empty fields in a table specially. If you don't like that, put a single ~ in that field.

A more complicated example:

type style
smart red short
rather silly puce tall

To create certain effects you can employ the \xmlattributes command:

gnats gram $13.65
each .01
gnu stuffed 92.50
emu 33.33
armadillo frozen 8.99

As an alternative for creating cells spanning multiple rows, you could check out the multirow package in the contrib directory.

Tabbing

A weak implementation of the tabbing environment is available if the HTML level is 3.2 or higher. It works using HTML <TABLE> markup, which is a bit of a hack, but seems to work well for simple tabbing environments.

The only commands implemented are \=, \>, \\, and \kill.

Here is an example:

while n < (42 * x/y)
if n odd
output n
increment n
return TRUE

Simulating typed text

The verbatim environment and the \verb command are implemented. The starred varieties are currently not implemented. (The implementation of the verbatim environment is not the standard LaTeX implementation, but the one from the verbatim package by Rainer Schöpf).

Furthermore, there is another, new environment example. example is also useful for including program listings or code examples. Like verbatim, it is typeset in a typewriter font with a fixed character pitch, and obeys spaces and line breaks. But here ends the similarity, since example obeys the special characters \, {, }, and %. You can still use font changes within an example environment, and you can also place hyperlinks there. Here is an example:

   To clear a flag, use
   \begin{example}
     {\back}clear\{\var{flag}\}
   \end{example}

(The example environment is very similar to the alltt environment of the alltt package. The difference is that example obeys the % character.)


Otfried Cheong, July 13, 2004

Moving information aroundTopConditional CompilationCarrying onContentsIndex