Perl Conditionals - The Unless Statement (
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The Unless Statement is the opposite of the If statement in that it asks if a condition is false, and executes the code unless the condition is true.
#!/usr/bin/perl
$my_iq = 1000;
$your_iq = 90;
unless ($your_iq > $my_iq)
{
print "My brain is enormous and far superior to your own!";
}
In the above code, the program will print out the sentence: "My brain is enormous and far superior to your own!" every time, unless $you_iq is greater than $my_iq.
Getting Loopy
Near the end of the day I always get a little loopy; I can't think straight and words just come out wrong. But I'm getting off topic here. Loops in code are something completely different.
The purpose of a loop is to loop a piece of code so that you don't have to type it over a billion times. Let's take a look at the For Loop:
#!/usr/bin/perl
for ($count =1; $count<10; $count++)
{
print "I R THE GREATEST!n";
}
The above code created a variable name $count and assigned an initial value of 1. It also has a part that tells it to increment the value of $count by +1 ($greatness++) and to do so until the value of $count is 10 or greater ($count<10). So long as the value of $count is less than 10, the following will print to the screen:
I R THE GREATEST!
I R THE GREATEST!
I R THE GREATEST!
I R THE GREATEST!
I R THE GREATEST!
I R THE GREATEST!
I R THE GREATEST!
I R THE GREATEST!
I R THE GREATEST!
If we were working with numbers we could have also just assigned a numeric value to $count and have it do this:
#!/usr/bin/perl
for ($count =1; $count<10; $count++)
{
print "$countn";
}
That would print out the following to your screen:
1
2
3
4
5
6
7
8
9
The For Loop loops for the number of times you tell it to.
