Re: UNLESS Statement Equivalent

On 11-3-2013 22:32, Angela Barone wrote:
> 	I'm looking for an 'unless' statement, but as far as I can tell, PHP doesn't have one.  Hopefully someone can help me rewrite my statement.
>
> 	In English, I want to say: "always do something UNLESS these 3 conditions are met".
>
> 	The best I've been able to come up with in PHP is this:
>
> if ( ($current_page == $saved_page) and ($current_ip == $saved_ip) and ($current_dt < ($saved_dt + 3600)) ) {
> 	return;
> } else {
> 	$query  = "UPDATE `table` SET `hits` = '$count', `agent` = '$agent', `ts` = '$date_time'  WHERE `page` = '$page'";
> 	$result = mysql_query($query) or die ('Error! -- ' . mysql_error());
> }
>
> 	However, I've read where this is not really acceptable.  Can someone help me eliminate the 'else' portion of this if statement?
>
> Thank you,
> Angela
>
> P.S.  I realize the above isn't complete code but it should still be clear.  If not, let me know.
>

Logically, unless means the same as  if not. As long as you condense 
your entire expression to a single boolean result, the only thing you 
would need to do is negate it to create your unless-statement.

In code, this would mean:
unless ( $a )
=
if ( !$a )

or to show it in a more clear way:
unless ( $a and $b )
=
if ( ! ($a and $b) )

So in simple terms, just stick a ! (or the keyword not) in front of your 
expression, and you'll have exactly what you want:
if( not ( ($current_page == $saved_page) and ($current_ip == $saved_ip) 
and ($current_dt < ($saved_dt + 3600) ) ) {