Re: Throwable::addSuppressed()

On 07/28/2015 04:51 PM, Markus Malkusch wrote:

Hi PHP So I read that there's this Throwable interface coming. Great! How about extending it with one further method: void Throwable::addSuppressed(Throwable exception) Semantic is the same as Java's Throwable.addSuppressed()¹. Why? Well consider a code fragment which wants to close a resource during an exception: } catch (Exception $e1) {

     try {
         $resource->close();
         throw $e1;

     } catch (ResourceException $e2) {
         // The information about $e2 is lost.
         throw $e1;
     }

} Currently PHP has no method to propagate both $e1 and $e2. With Throwable::addSuppressed() $e2 could be added as a suppressed exception to $e1: } catch (Exception $e1) {

     try {
         $resource->close();

     } catch (ResourceException $e2) {
         e1->addSuppressed($e2);

     }
     throw $e1;

} To make this information useful (for e.g. a logger) there's one further method needed: Throwable[] Throwable::getSuppressed() So PHP, what do you think, might a RFC find acceptance? Best wishes Markus Malkusch [1]: http://docs.oracle.com/javase/8/docs/api/java/lang/Throwable.html#addSuppressed-java.lang.Throwable-

Interesting thought, but how is this different than including a previous throwable and throwing a new, more descriptive exception? } catch (Exception $e1) {

     try {
         $resource->close();
     } catch (ResourceException $e2) {
         // Pass in $e2 as the previous exception in the chain.
         throw new ResourceFailedException($e1->getMessage(), $e1->getCode(), $e2);
     }

} What you're describing doesn't seem like a common use case. Also, this is pretty nitpicky, but the above code might fit better with a finally block when closing resources: try {

    // Do something with $resource here...

} finally {

     $resource->close();

} -- Stephen Coakley