<?php

DEFINE('LIMIT', 1000000);

$world = "World";

$start = microtime();

for ($i = 0; $i < LIMIT; $i++) {
 $s = 'Hello, '.$world.', how are you?';
}

$took = microtime() - $start;
echo("String append took [{$took}]\r\n");

$start = microtime();

for ($i = 0; $i < LIMIT; $i++) {
 $s = 'Hello, {$world}, how are you?';
}

$took = microtime() - $start;
echo("Complex string syntax took [{$took}]\r\n");