where the value of $i goes ?

[vishwavivek]

hi there,

look at this code .... simple string comparision code ......

<?php

$str1="ab";
$str2="aB";

if(($i = strcmp($str1,$str2)) == 0)
echo "Returned : $i and the Strings are equal";
else
echo "Returned : $i and the Strings are not equal";

?>

this works fine .... and returns that strings r not equal and also returns value of $i i.e. 1 (in this case)

BUT ... my question is .... if we remove the BRACES, then where the value of $i goes ?? ... i mean ....

<?php

$str1="ab";
$str2="aB";

if($i = strcmp($str1,$str2) == 0)
echo "Returned : $i and the Strings are equal";
else
echo "Returned : $i and the Strings are not equal";

?>

look at the braces around ........ ($i = strcmp($str1,$str2)) ..... i removed the outer braces in the second code ....

now, the answer is same i.e. strings r not equal .... BUT it doesn't print the value of $i .... where is goes .....

i tried using isset($i) to find out that whether $i is setted or not ?? then it prints true

can any one explain this thing ?? is this related to some operator precedence ... please explain .. i m not getting this by that view also

thanks in advance

viv

[mrhappiness]

in the first part you assign the return value of strcmp to $i and compare this with 0

as the return value of $i is 1 => $i is 1 as well

since 1 == 0 evaluates to false the else branch will be executed

in the second part you compare the return value of strcmp with 0 and assign the result to $i

as strcmp returns 1 => $i = 1 == 0 => $i = false => the else branch will be executed but $i dos not contain the value 1 but the value false and

echo false;

will not produce any output

got it?

[vishwavivek]

Thanks 🙂

i was confused by the value returned by isset($i)

i assumed that $i=false will be treated as a variable not setted, i was misunderstood it with NULL

Thanks again

vivek

[vishwavivek]

u explained it very clearly 🙂 thanks again 🙂