Situations like that have gotten me started down the road of testing defined-ness or existence, never truth (except for something that specifically is supposed to be a boolean, usually because it begins with $is_).

It's also kinda like the C-programmer's idiom of if ( 5 == var ) instead of if ( var == 5 ). That protects against the accidental if ( var = 5 ).

My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re: Keep Those Conditionals Tight by dragonchild
in thread Keep Those Conditionals Tight by friedo

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