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2.7. The if Control Structure

Once you can compare two values, you'll probably want your program to make decisions based upon that comparison. Like all similar languages, Perl has an if control structure:

if ($name gt 'fred') {
  print "'$name' comes after 'fred' in sorted order.\n";
}

If you need an alternative choice, the else keyword provides that as well:

if ($name gt 'fred') {
  print "'$name' comes after 'fred' in sorted order.\n";
} else {
  print "'$name' does not come after 'fred'.\n";
  print "Maybe it's the same string, in fact.\n";
}

Unlike in C, those block curly braces are required around the conditional code. It's a good idea to indent the contents of the blocks of code as we show here; that makes it easier to see what's going on. If you're using a programmers' text editor (as discussed in Chapter 1, "Introduction"), it'll do most of the work for you.



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