note 102346 deleted from language.operators.string by thiago

Note Submitter: frank at interactinet dot com 

----

using single quotes and concatenation can be faster than using double quotes.

<?php

$y = 'this is a test';

$x = "$y to see how concat compares";
// double quote test average for 10000 iterations: 0.001625 sec

$x = $y.' to see how concat compares';
// single quote plus concat test average: 0.001522 sec
?>

The concatenation was approx 7% faster. 
Surprisingly, with more variables the concatenation becomes even better at 35% faster:

<?php

$x = "$y to see how concat compares $y";
// 0.002456641 sec average

$x = $y.' to see how concat compares'.$y;
// 0.00181675 sec average

?>

So, it is better to create strings with single quotes.

Here was the benchmark code:
<?php

for($j=0;$j<10;$j++)
{
	$s = microtime(TRUE);
	for($i=0;$i<10000;$i++)
	{
		$x = "$y to see how concat compares $y";
	}
	echo microtime(TRUE)-$s,'<br>';
}

echo '<br><br><br>';

for($j=0;$j<10;$j++)
{
	$s = microtime(TRUE);
	for($i=0;$i<10000;$i++)
	{
		$x = $y.' to see how concat compares'.$y;
	}
	echo microtime(TRUE)-$s,'<br>';
}
exit();
?>