I find that unless() has a very small useful footprint. Sure, may be OK when there is a single condition:

unless ($things_went_wrong) { # do some stuff }

[download]

But, when there are multiple conditions, it gets tougher to keep straight: 

unless ($result < $HIGHEST_VALUE && ! $bad_results{$result}) { # stuff
+ }

[download]

And then there is this legal, but almost much harder to follow, control structure: 

unless ($result) {
    ## Do some stuff
}
elsif (!$result) {
    ## Do some other stuff
}
else {
    ## yet other stuff... 
}

[download]

In the end, 'unless(') is just a way to type 'if (!)', but with more keystrokes and it has a better chance of making your brain hurt. And, you never have to worry about decoding double negatives, or re-writing them if your control statements need to grow down the line if you just use 'if (!)'.

In reply to Re^3: How to no goto or gosub by shilo
in thread How to no goto or gosub by oldcity

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