#!/usr/bin/perl
#! To operate, be sure to add user execute permissions to file
#! For Windows, you may need to change the path settings to 
#! include the per compiler. 

#! Poem extracts is "To the Evening Star" by Bill Blake

#! Making a hash. Format is [key] => [value].

%EveningStar = (
	"Opening_Line" => "Thou fair-hair'd angel of the evening",
	"Second_Line" => "Now, whilst the sun rests on the mountains, light",
	"Line3" => "Thy bright torch of love; thy radiant crown",
	"Line4" => "Put on, and smile upon our evening bed!",
	"Author" => "-William_Blake",
	);

print $EveningStar{Opening_Line};
print "\n";
print "\n";

#! Looping through all the values of a hash (Note Perl doesn'r guarantee line order:

while ( ($key, $value) = each %EveningStar ) {
	print "$value\n";
	};

print "\n";
print "\n";


#! Checking if a key exists, using the exist function:

if (exists $EveningStar{"Author"}) {
	print $EveningStar{Author}
};

print "\n";
print "\n";

#!Another array, from the book "Learning Perl";

$books{"Fred"} = 3;
$books{"wilma"} = 1;
$books{"barney"} = 0;
$books{"pebbles"} = undef;

while ( ($key, $value) = each %books){
		if ($value > 0) {
		print "$key has at least $value books checked out.\n";
						}
}