// Integers
echo 1 <=> 1; // 0
echo 1 <=> 2; // -1
echo 2 <=> 1; // 1
// Floats
echo 1.5 <=> 1.5; // 0
echo 1.5 <=> 2.5; // -1
echo 2.5 <=> 1.5; // 1
// Strings
echo "a" <=> "a"; // 0
echo "a" <=> "b"; // -1
echo "b" <=> "a"; // 1
echo "a" <=> "aa"; // -1
echo "zz" <=> "aa"; // 1
// Arrays
echo [] <=> []; // 0
echo [1, 2, 3] <=> [1, 2, 3]; // 0
echo [1, 2, 3] <=> []; // 1
echo [1, 2, 3] <=> [1, 2, 1]; // 1
echo [1, 2, 3] <=> [1, 2, 4]; // -1
// Objects
$a = (object) ["a" => "b"];
$b = (object) ["a" => "b"];
echo $a <=> $b; // 0
// 原本這樣寫
$username = (isset($_POST['username']) ? $_POST['username'] : 'guest');
// PHP 7.0 現在可以這樣寫
$username = $_POST['username'] ?? 'guest';
function handle_age_calc($birthdate_str): int
{
/* do some birth-age calculation */
return $intAge;
}
yum groupinstall 'Development Environment'
yum whatprovides autoconf automake
yum install libxml*
wget http://tw1.php.net/distributions/php-7.0.0.tar.gz
tar xvfz php-7.0.0.tar.gz
cd php-7.0.0
./buildconf
./configure
make -j8
./sapi/cli/php --version