Hmm. I would say that there are much better defensive programming moves that you can make with your snippet.

You posted 

for (@$Courses) {
        if ($Course = CheckCourse($_)) {
            print PageCourseInfo($Course);
            $count ++;
        }
        else {
            last;
        }
        last if $count >= 10;
}

[download]
Which I would probably not write in the same way at all. First you are using an assignment in a conditional. While this is not wrong personally I think its a bad call most times. Reason being that its easy to think that youve made the "=" instead of "==" typo. Second point would be that when writing an if/else block its usually a good idea to put the smaller block first, changing the condition as is necessary. Third instead of doing your >= you could have been even simpler and used <. Anyway, heres how I would have written the same thing 
for (@$Courses) {
        my $Course = CheckCourse($_);
        last unless $Course;

        print PageCourseInfo($Course);

        last unless ++$count < 10;
}

[download]

Yves / DeMerphq
--
When to use Prototypes?

In reply to Re: Defensive Programming by demerphq
in thread Defensive Programming by George_Sherston

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