Printing Variables - Perl

We've learned in the past to work with variables, and I know this is a bit redundant, but keep in mind that this article is more of a cheat sheet for different ways of manipulating text.

We store text in variables and print it like so: 

!/usr/bin/perl

$a='Apple';

$b='Jacks';

print "The best cereal in the world is $a $b.";

This prints out:

  The best cereal in the world is Apple Jacks.

One note of warning: in the previous section we talked about using single and double quotes together. This method does not work the same when dealing with variables. Observe the following:

#!/usr/bin/perl

$a='apple';

$b='jacks';

print 'The best cereal in the world is $a $b.';

This will print out:

  The best cereal in the world is $a $b.

Which of course is not what we were hoping for.

To get it to print the values inside the variables, we have to use double quotes, like so:

#!/usr/bin/perl

$a='Apple';

$b='Jacks';

print "The best cereal in the world is $a $b.";

Which results in the proper print-out (and a very true statement):

  The best cereal in the world is Apple Jacks.

The reason why this occurs is simple enough. When Perl sees a single quotation mark, it does not interpret; when it sees double quotation marks, it does.

Note that you can store an unlimited amount of variables within your double quoted string:

#!/usr/bin/perl

$a="Hello";

$b="how";

$c="are";

$d="you";

$e="doing";

$f="today?";

$Question="$a $b $c $d $e $f";

print $Question;

Which gives us:

  Hello how are you doing today?