RE: [PHP] Re: UNLESS Statement Equivalent

> -----Original Message-----
> From: Maciek Sokolewicz [mailto:[email protected]] On Behalf Of
> Maciek Sokolewicz
> Sent: 11 March 2013 22:44
> 

> 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) ) ) {

Whilst this is true as far as it goes, I would suggest applying deMorgan's laws
to simplify slightly to

   if ( ($current_page != $saved_page) or ($current_ip != $saved_ip) or ($current_dt >= ($saved_dt + 3600) ) )

Also, the keyword versions of the Boolean operators are very low
priority, which is why you need all those extra parentheses -- if
you switch to the symbolic versions, you can leave all the internal
parentheses out to give:

   if ($current_page != $saved_page || $current_ip != $saved_ip || $current_dt >= $saved_dt + 3600)


Cheers!

Mike

-- 
Mike Ford,
Electronic Information Developer, Libraries and Learning Innovation,  
Portland PD507, City Campus, Leeds Metropolitan University,
Portland Way, LEEDS,  LS1 3HE,  United Kingdom 
E: [email protected]     T: +44 113 812 4730





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