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Lesson 14
Objective
 Perl arrays
Learn how to initialize and access data in an array.
   
Arrays are distinguished by the @ ("at" sign) introducing the name:
@presidents

You can initialize an array by assigning a list of values to it: 
@presidents = ( 'Franklin', 'Harry', 'Dwight', 'John', 
'Lyndon', 'Richard', 'Gerald', 'Jimmy', 
'Ronald', 'George', 'Bill', );
Alternately, you can use barewords with the qw operator:
@presidents = qw( Franklin Harry Dwight John 
Lyndon Richard Gerald Jimmy Ronald George Bill );
Barewords in Perl
Barewords are words that have no other interpretation and are treated as if they were a quoted string.
Now you have an array that contains the first names of some presidents.
Accessing the array elements
The elements in an array are numbered, begining with zero. Each of these numbers is referred to as an index into the array. The array we just defined looks something like this:
Array diagram
Once you have the array declared, you can access individual elements with the subscript operator:
$presidents[3]   # John
The number within the brackets is the index into the array. You can use any numeric value to index the array:
$prez_no = 3;
$presidents[$prez_no];    # John
You use a $ here because the value you are extracting from the array is a scalar.
You can use the value of an array even within another string:
print "$presidents[3]\n";
Here are some Perlisms for arrays.
Create Array - Exercise
Click the Exercise link below to write a small program using an array and join.
Create Array - Exercise
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