Guide to LaTeX (4th Edition) (Tools and Techniques

4.9. Printing literal text 111
\verb=\emph{words of text}= \emph{words of text}
\verb*=\emph{words of text}= \emph{words of text}
where the first character after \verb or \verb* (here =) is the delimiter,
such that all text up to the next occurrence of that character is printed
literally. This character may not appear in the literal text, obviously.
In contrast to the behavior in the verbatim environment, the literal
text must be all on one line in the input text, otherwise an error message
is printed. This is to indicate that you just might have forgotten to repeat
the delimiting character.
Important: neither the verbatim environment nor the \verb command
may be used in an argument of any other command!
Exercise 4.16: Reproduce some input lines from this book as literal text.
4.9.1 Extension packages for literal text
Package: The standard package alltt (Section B.5.3, page 392) provides an alltt
alltt environment that also prints its contents literally in a typewriter font,
except that the characters \ { } retain their normal meaning. Thus LAT EX commands can be included within the literal text. For example,
\begin{alltt}
Underlining \underline{typewriter}
text is also possible.
Note that dollar ($) and
percent (%) signs are
treated \emph{literally}.
\end{alltt}
Underlining typewriter
text is also possible.
Note that dollar () and
percent (%) signs are
treated literally.
Package: The standard package shortvrb (Section B.5.3, page 393) offers a
shortvrb shorthand for the \verb command. After issuing \MakeShortVerb{\|},
one can print short literal text with |text|. The counter command
\DeleteShortVerb{\|} then restores the original meaning to |. Any
character may be temporarily turned into a literal switch this way.
Package: One problem with the verbatim environment is that the entire litverbatim
eral text is input and stored before processing, something that can lead
to memory overflows. The verbatim package in the tools collection
(Section B.5.4, page 396) re-implements the environment to avoid this
problem. A minor drawback is that there must not be any other text on
the same line as the \end{verbatim}.
The verbatim package offers two other extra features. It provides
a comment environment that simply ignores its contents, as though
each line started with a % sign (Section 4.11). And it adds a command
\verbatiminput{filename} to input the specified file as literal text. This
is useful for listing actual computer programs rather than copying them
into the LAT EX file.