@var
{metasyntactic-variable}Use the @var
command to indicate metasyntactic variables. A
metasyntactic variable is something that stands for another piece of
text. For example, you should use a metasyntactic variable in the
documentation of a function to describe the arguments that are passed
to that function.
Do not use @var
for the names of particular variables in
programming languages. These are specific names from a program, so
@code
is correct for them (see code). For example, the
Emacs Lisp variable texinfo-tex-command
is not a metasyntactic
variable; it is properly formatted using @code
.
Do not use @var
for environment variables either; @env
is correct for them (see the next section).
The effect of @var
in the Info file is to change the case of the
argument to all upper case. In the printed manual and HTML output, the
argument is printed in slanted type.
For example,
To delete file @var{filename}, type @samp{rm @var{filename}}.
produces
To delete file filename, typerm
filename.
(Note that @var
may appear inside @code
,
@samp
, @file
, etc.)
Write a metasyntactic variable all in lower case without spaces, and use hyphens to make it more readable. Thus, the Texinfo source for the illustration of how to begin a Texinfo manual looks like this:
\input texinfo @@setfilename @var{info-file-name} @@settitle @var{name-of-manual}
This produces:
\input texinfo @setfilename info-file-name @settitle name-of-manual
In some documentation styles, metasyntactic variables are shown with angle brackets, for example:
..., type rm <filename>
However, that is not the style that Texinfo uses. (You can, of
course, modify the sources to texinfo.tex
and the Info formatting commands
to output the <...>
format if you wish.)