Changeset 2410

Timestamp:

Nov 23, 2004, 1:37:29 PM (22 years ago)

Author:

jhoblitt

Message:

add loading modules

File:

• trunk/doc/misc/perlCodeConventions.tex (modified) (2 diffs)

trunk/doc/misc/perlCodeConventions.tex

@@ -1 @@
-%%% $Id: perlCodeConventions.tex,v 1.31 2004-11-23 23:20:38 jhoblitt Exp $
+%%% $Id: perlCodeConventions.tex,v 1.32 2004-11-23 23:37:29 jhoblitt Exp $
 \documentclass[panstarrs]{panstarrs}
 
@@ -1117 +1117 @@
 \end{verbatim}
 
+\subsubsection{Loading Modules}
+
+Modules may be loaded with an optional version requirement.  This is
+particularly useful for modules that exist in the Perl core but have newer
+versions available on CPAN.
+
+\begin{verbatim}
+    use Foo;                            # Correct
+    use Foo 0.02;                       # Correct
+\end{verbatim}
+
+Don't use \code{require} to prevent a module from exporting symbols into the
+caller's namespace.  Instead, provide \code{use} with an empty parameter list.
+
+\begin{verbatim}
+    use Foo qw();                       # Correct
+    use Foo ();                         # Correct
+    require Foo;                        # AVOID!
+\end{verbatim}
+
+This also works with a minimum module version requirement.
+
+\begin{verbatim}
+    use Foo 0.02 qw();                  # Correct
+\end{verbatim}
 
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