0.5.1. Programming Conventions

We give lots of examples, most of which are pieces of code that should go into a larger program. Some examples are complete programs, which you can recognize because they begin with a #! line. We start nearly all of our longer programs with:

#!/usr/bin/perl -w
use strict;

or else the newer:

#!/usr/bin/perl 
use strict;
use warnings;

Still other examples are things to be typed on a command line. We've used % to show the shell prompt:

% perl -e 'print "Hello, world.\n"'
Hello, world.

This style represents a standard Unix command line, where single quotes represent the "most quoted" form. Quoting and wildcard conventions on other systems vary. For example, many command-line interpreters under MS-DOS and VMS require double quotes instead of single ones to group arguments with spaces or wildcards in them.