4.2.3 Block hooks

It is also possible to override LaTeX environments that are responsible for Texinfo's block environments such as @examples and @displays.

As you can see in the following list, the default values for most block hooks derive from the LaTeX environment `{display}'. See preamble.mod.xsl for its definition. It assures proper indentation in a nested environment (such as an enumeration). Moreover, it allows for additional indentation via its optional parameter in [...]. The default indentation is \standardmargin (equal to \parindent).

If you want to override the block hook name, say

     \renewenvironment{nameHook}{opening commands}%
         {closing commands}

It is advisable, though not necessary, to use the {display} environment somewhere in the new definition.

As an example, let's assume you wanted to give all @examples a grey background. You achieve this by adding this to your LaTeX config file:

     \usepackage{color,framed}
     \definecolor{shadecolor}{gray}{0.75}
     \renewenvironment{exampleHook}{%
       \begin{shaded}\begin{display}\ttfamily}%
         {\end{display}\end{shaded}}

You can also re-define the {display} environment itself to change the layout of most block types. However, you must be careful with that. See its definition in preamble.mod.xsl for further information.

List of all block element hooks

quotationHook

Default: {\begin{quote}}{\end{quote}}

copyingHook

Default: {\begin{quote}}{\end{quote}}

verbatimHook

Default: {\begin{display}[0pt]\ttfamily}{\end{display}}

exampleHook

Default: {\begin{display}\ttfamily}{\end{display}}

lispHook

Default: {\begin{display}\ttfamily}{\end{display}}

displayHook

Default: {\begin{display}\relax}{\end{display}}

formatHook

Default: {\begin{display}[0pt]}{\end{display}}

smallexampleHook

Default:

          {\begin{small}\begin{exampleHook}}%
          {\end{exampleHook}\end{small}}
     

smalldisplayHook

Default:

          {\begin{small}\begin{displayHook}}%
          {\end{displayHook}\end{small}}
     

smallformatHook

Default:

          {\begin{small}\begin{formatHook}}%
          {\end{formatHook}\end{small}}
     

smalllispHook

Default:

          {\begin{small}\begin{lispHook}}%
          {\end{lispHook}\end{small}}
     

flushleftHook

Default: {\begin{flushleft}}{\end{flushleft}}

flushrightHook

Default: {\begin{flushright}}{\end{flushright}}

groupHook

Default: {\begin{samepage}}{\end{samepage}}

cartoucheHook

Default:

          {\begin{center}\shadowbox\bgroup
             \hbox to \hsize\bgroup\begin{minipage}{\hsize}}%
          {\end{minipage}\hss\egroup\egroup\end{center}}
     

\centerHook

Default: \centerline{#1}

Attention! Although this is a block hook by layout, it is not so in terms of its LaTeX realisation. In fact it is a LaTeX macro as those inline hooks, see Overriding LaTeX hooks.

Note that if you activate syntax highlighting (see Command line options), some @lisp and @smalllisp blocks will be typeset using LaTeX's `listings' package. This cannot be included in a hook. However, the `lispHook' is still wrapped around it.