and && or ||

[arnage]

"and" is not the same like && , also, "or" is not same like ||

&& is higher priority than "and" , also, || is higher priority than "or".

For example:

$a && $b || $c; 

is not the same like:

$a and $b || $c; 

the first thing is:
(a and b) or c

the second:
a and (b or c)

Because || has got a higher priority than and, but less than && .

Using always [ && and || ] or [ AND and OR ] would be okay, but than you should at least respect the following:

$a = $b && $c;
$a = $b and $c; 

the first code will set $a to the result of the comparison $b with $c, both have to be true, while the second code line will set $a like $b and THAN - after that - compare the success of this with the value of $c .

[CreativityKills]

i dnt undastand wth u talkn about. I use and and or, easier to read.

[mFreak]

i dnt undastand wth u talkn about. I use and and or, easier to read.

Its like mats, look it this way

and is +
or is -
&& is *
|| is /

you probably know that is you have an expresion a+b*c=d its the same as a+(b*c)=d not the (a+b)*c=d. the * simply have a priority over + and is checked first. same is with 'and' and '&&'

[arnage]

i dnt undastand wth u talkn about. I use and and or, easier to read.

Look at this example from my site script:

if (!empty($a) and check_it($a) || strlen($a) != 32) { exit(errors()); } 

if u write it like this:

if (!empty($a) && check_it($a) || strlen($a) != 32) { exit(errors()); } 

index page will not open, this is gonna end up with exit; always because of priority. Its not the same.

[subzero]

Most of my scripts use || and && i never used (AND OR OR)

[arnage]

Me too until i came across this particular problem, when i researched a bit and used only once "and" in the script insted &&.

[CreativityKills]

Look at this example from my site script:

if (!empty($a) and check_it($a) || strlen($a) != 32) { exit(errors()); } 

if u write it like this:

if (!empty($a) && check_it($a) || strlen($a) != 32) { exit(errors()); } 

index page will not open, this is gonna end up with exit; always because of priority. Its not the same.

i undastand bt really it boils down to coding style. Me i usually take note of that, so i make use of brackets to tell php which i wana run 1st.

// this
$calc = 66 + 20 * 8;

// is not
$calc = 66 + (20 * 8);

// ur examply my way
if ( ( isset($a) AND ! empty($a) AND check_it($a) ) OR strlen($a) !== 32) {
exit(errors());
} 

[arnage]

Thats a different thing mate, like step further, i just talking about this.

PHP: Logical Operators - Manual