unless statements

Unless statements allow you to say unless something is true do this. For example:

$value=20;
unless($divisor==0){      #so long as the $divisor isn't equal to 0
  $value=$value/$divisor; #go ahead and divide $value by $divisor
} else {
  $divisor=1;             #otherwise set $divisor to 1
}

If you've got that I suggest you take a look at while loops

Comment on unless statements

Replies are listed 'Best First'.
Re: unless statements by htoug (Deacon) on Feb 08, 2005 at 11:09 UTC
It is a matter of taste (and style), but I only use `unless` without the `else`-clause. If you have the `else`, then you could just as well use a normal `if` and get better readability - it's more like waht everyone is used to. But in a standalone `if (!(some_complicated_expression))` the use of `unless` lets you remove one pair of parenthesis and lets the poor smuck reading the code have one less thing to worry about. I would rewrite your example as `$value=20; if ($divisor!=0){ #so long as the $divisor isn't equal to 0 $value=$value/$divisor; #go ahead and divide $value by $divisor } else { $divisor=1; #otherwise set $divisor to 1 }` [download] Now the statement says the same as the comment (in your code it should have been `#unless the $divisor isn't equal to 0` - 'so long' indicates a repetition IMHO).	[reply] [d/l] [select]
Re^2: unless statements by Anonymous Monk on Jul 01, 2005 at 16:15 UTC
Hello , well i think unless is a loop and things like : if ($divisor!=0){ doesn't work rather than using unless if will procedes the action for one time but unless will keep procedes the same things unless the statment goes wrong that's what i think	[reply]
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