- version_compare: documentation ( source)
- trigger_error: documentation ( source)
<?php
class Coalescing
{
protected $attributes = [
'attribute1' => 'value1',
];
public function __get($name)
{
print "GET\n";
if (array_key_exists($name, $this->attributes)) {
return $this->attributes[$name];
}
trigger_error("Property $name does not exist");
return null;
}
public function __isset($name)
{
print "ISSET\n";
return array_key_exists($name, $this->attributes);
}
}
$coal = new Coalescing();
version_compare(PHP_VERSION, "7.0", ">=") && eval('var_dump($coal->attribute1 ?? "default");');
//GET
//string(6) "value1"
version_compare(PHP_VERSION, "7.0", ">=") && eval('var_dump($coal->attribute2 ?? "default");');
//GET
//PHP Notice: Property attribute2 does not exist in /var/www/html/test.php on line 23
//PHP Stack trace:
//PHP 1. {main}() /var/www/html/test.php:0
//PHP 2. Coalescing->__get() /var/www/html/test.php:41
//PHP 3. trigger_error() /var/www/html/test.php:23
///var/www/html/test.php:41:
//string(7) "default"