There must be a better way (php, string)

Question

I want to display a user's firstname if they gave us one, otherwise their email. The code below functions, but I don't like how it takes so many lines, I vaguely recall some way of maybe doing this with OR? I have (essentially):

if ($firstname == "")
{
$name   = $email;
}else{
$name = $firstname;
}
echo $name;

Answer 1

echo ($firstname) ? $firstname : $email;

Answer 2

较短的版本（PHP 5）

echo ($firstname ? : $email);

Answer 3

这是一个不常见但有时有用的构造（作为?:语法的替代）：

 $name = $firstname   OR   $name = $email;