In my experience, my own particular brand of defensive programming is to defend me from myself. I can almost guarantee that most of my mistakes come at 2:00AM, after an evening of caffiene jolts and with music blaring into my headphones.

My own list of defenses are probably very similar to most of the other monks (I have seen quite a few) so I won't go into much detail. Heres one example of the things I do: 
# Number 1: the trailing return
sub blah
{
 if($somevar == $somevalue)
 {
    return $this;
 }
 else
 {
   return $that;
 }
 return;
}

[download]

I had an argument with my boss for a while about doing this. But it does nothing, harms nooone so why not (well that was my argument :P).

I think it is easy to confuse defensive programming with secure programming but I see them as two separate disciplines.

Defensive programming should, in my opinion, be about how you program. Thus it allows you to affect the design of the program as well as how you implement it. After all, if an algorithm or code snippet (more likely) goes against your own brand of superstition then who would honestly not re-write it? I know that the first thing I would do with code from another person is go through it with a fine toothcomb.

In reply to Re: Defensive Programming by simon.proctor
in thread Defensive Programming by George_Sherston

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