delete in PHP

On 1 Jun 2004 at 16:50, Florian Schaper wrote:

object's

references of

have an

There has been a heated discussion on this topic and the conclusion was to drop delete. Please search the archives for pros and cons.

On Tue, 2004-06-01 at 16:50, Florian Schaper wrote:

In comparison to the proposed "delete", unset() only decreases the refcount. Have a look at the following examples: $ php-dev -r 'class Object { function __destruct() { echo "Destroyed\n"; }} $o= new Object(); unset($o); echo "Shutting down\n";' Destroyed Shutting down $ php-dev -r 'class Object { function __destruct() { echo "Destroyed\n"; }} $o= new Object(); $o2= $o; unset($o); echo "Shutting down\n";' Shutting down Destroyed In the second example, the destructor is not called until *after* shutdown. This is the small but noticeable difference between what Florian wants and what we currently provide. While I agree this could be interesting, I'm opposed to a keyword named "delete". Keywords may not be used as regular method names and a new keyword "delete" would add more BC breaks for people using methods called delete(). This: class DBConnection { function insert() { } function update() { } function select() { } function delete() { } } is an example which can be seen in numerous applications. Then again, why doesn't unset() do this? That seems kind of inconsistent with the object-handle-pass-by-value semantics we have in PHP5. For the time being, using reference operators and setting the instance to NULL gives you a workaround: $ php-dev -r 'class Object { function __destruct() { echo "Destroyed\n"; }} $o= new Object(); $o2= &$o; $o= NULL; echo "Shutting down\n";' Destroyed Shutting down Interesting enough (from a user's pov, not the Engine's), unset() will not do the job: $ php-dev -r 'class Object { function __destruct() { echo "Destroyed\n"; }} $o= new Object(); $o2= &$o; unset($o); echo "Shutting down\n";' Shutting down Destroyed (neither will omitting the & in the first solution). - Ti "back to references after all?" mm