The problem with unless() is just that people get lost in double negatives and precedence.

Some people do certainly but in my experience it's not a "constant sources of bugs". Certainly not enough of a problem for me to drop the improved clarity I see when the construct is used well.

The problem with trailing if() is this.

I'd count that a perl bug, and since perl 5.9.1 we'll get a warning for this "dubious and deprecated construct". I've never seen this in live code, and have never been tempted to write anything that looked like it. If this is the only problem then I'm not worried :-)

In reply to Re^4: Control Structures by adrianh
in thread Control Structures by artist

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