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Sometimes you may find yourself having to
write
almost the same piece of \HyperName{}
text many times. Thankfully, there is a command to ease
the work.
It is the {\tt \\newcommand} command and provides
a macro facility for \HyperName{}.
In this way, you can give a short name to a sequence of \HyperName{}
text and use that name to include the sequence in your pages.
The way this works is the following
\beginImportant
\newline
\centerline{{\tt \\newcommand\{\\{\it name}\}[{\it number of arguments}]\{{\it \HyperName{} text}\}}}
\endImportant
and here is an example from {\bf util.ht}
\beginImportant
\newline
{\tt \\newcommand\{\\spadsig\}[2]\{\\spadtype\{\#1\} \{\\tt ->\} \\spadtype\{\#2\}\}}
\newline
{\tt \\newcommand\{\\spadtype\}[1]\{\\lispdownlink\{\#1\}\{(|spadType| '|\#1|)\}\}}
\endImportant

You see that a macro's definition can invoke another.
Don't create a circular definition though!
Notice how the arguments of the macro are used
in the definition. The {\tt \#{\it n}} construct
is the place--holder of the {\it n}'th argument.

To use the macro, just treat it as an ordinary command.
For instance
\beginImportant
\newline
{\tt \\spadsig\{Integer\}\{List Integer\}}
\endImportant
displays and acts like this
\beginImportant
\newline
\spadsig{Integer}{List Integer}
\endImportant

The best way to familiarise yourself to
macros is to study the macros defined in
\centerline{
{\bf \env{AXIOM}/share/hypertex/pages/util.ht}
}
It is highly probable that a good many of them
will prove useful to you.
Clever use of macros will allow you to
create \HyperName{} text that can be
formatted by other programs (such as TeX).
The \Language{} User Guide was written
in such a way as to make translation in
\HyperName{} form and TeX form a mechanical process.




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