In PHP, what is an underlying reason of placing either boolean or null before identical comparison operator?
false === $value;
null === $value;
It seems to me that it is same as saying
$value === false;
Is it just a personal preference or there is a concrete reason why people do this?
It’s a convention to avoid the mistake of accidentally assigning a variable.
$value = false;
instead of
$value === false;
Answer：
This is sometimes referred to as Yoda-conditions, there’s a fun list of all such constructs and their unofficial names.
No there’s no real difference between $var === false or false === $var, some people claim it’s easier to see what is being checked for if the bool is the left operand, other hate it… In short: personal preference is what it is.
Answer：
It’s supposed to be quicker, but I can’t lay a hand on an authority saying this with a simple Google search. See:
http://forums.phpfreaks.com/topic/222939-is-there-a-difference-between-ifvar-false-and-iffalse-var/
for one opinion.
Tags: phpphp
