/**
* Implements the C# 'using' statement.
*
* Calls the supplied callable and, when done, disposes of the input object. This was
* originally pulled from gonzalo123's 'using' repo @ https://github.com/gonzalo123/using
*
* @param IDisposable $input An instance of an IDisposable class.
* @param callable $callback The callable function to use with the input class.
*/
function using(IDisposable $input, $callback = null)
{
$disposer = function ($input) {
$input->dispose();
};
try {
\call_user_func($callback, $input);
$disposer($input);
} catch (\Exception $e) {
$disposer($input);
throw $e;
}
}
/**
* Invokes a function for a disposable object and keeps sure that the
* IDisposable::dispose() method of it is called at the end of the invocation, even
* if an exception is thrown. s. https://msdn.microsoft.com/en-us/library/yh598w02.aspx
*
* @param callable $func The function to invoke.
* @param IDisposable $obj The disposable object.
* @param mixed ...$arg One or more additional argument for $func.
*
* @return mixed The result of $func.
*
* @throws ArgumentException $func is no valid callable / lambda expression.
* @throws ArgumentNullException $func is (null).
*/
public static function using($func, IDisposable $obj = null)
{
if (null === $func) {
throw new ArgumentNullException('func');
}
$func = static::asCallable($func);
try {
return \call_user_func_array($func, \array_merge([$obj], \array_slice(\func_get_args(), 2)));
} finally {
if (null !== $obj) {
$obj->dispose();
}
}
}