Can anybody tell the internal procedure of the below expression?
<?php echo '2' . print(2) + 3; ?>
// outputs 521
Can anybody tell the internal procedure of the below expression? <?php echo ‘2’ .
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Can anybody tell the internal procedure of the below expression?
<?php echo '2' . print(2) + 3; ?>
// outputs 521
Echo a concatenated string composed of:
The string ‘2’
The result of the function print(‘2’), which will return true, which gets stringified to 1
The string ‘3’
Now, the order of operations is really funny here, that can’t end up with 521 at all! Let’s try a variant to figure out what’s going wrong.
echo ‘2’.print(2) + 3;
This yields 521
PHP is parsing that, then, as:
echo ‘2’ . (print(‘2’) + ‘3’))
Bingo! The print on the left get evaluated first, printing ‘5’, which leaves us
echo ‘1’ . print(‘2′)
Then the left print gets evaluated, so we’ve now printed ’52’, leaving us with
echo ‘1’ . ‘1’ ;
Success. 521.
I would highly suggest not echoing the result of a print, nor printing the results of an echo. Doing so is highly nonsensical to begin with.