Req #32100 [Com]: Request 'finally' support for exceptions

From: Date: Fri, 18 Nov 2011 00:25:24 +0000
Subject: Req #32100 [Com]: Request 'finally' support for exceptions
References: 1  Groups: php.bugs 
Request: Send a blank email to php-bugs+get-165301@lists.php.net to get a copy of this message 
Edit report at https://bugs.php.net/bug.php?id=32100&edit=1

 ID:                 32100
 Comment by:         chiestand at salk dot edu
 Reported by:        ceefour at gauldong dot net
 Summary:            Request 'finally' support for exceptions
 Status:             Closed
 Type:               Feature/Change Request
 Package:            Feature/Change Request
 Operating System:   *
 PHP Version:        5.*
 Block user comment: N
 Private report:     N

 New Comment:

First, thank you everyone who has contributed to this bug report thread. Your 
insights have been incredibly useful.

I too vote for inclusion of "finally" into PHP. In my own particular situation I was 
able to solve my problem using Stroustrup's RAII pattern (thank you btsai). But I can 
imagine that in some cases creating a class for every resource used might be 
inconvenient.

I think ceefour really summed it up nicely back in 2005 with even more-ancient 
wisdom: "Be conservative with what you emit and be liberal with what you accept". 
Provide the tool, and let the coder decide what pattern to use.


Previous Comments:
------------------------------------------------------------------------
[2011-09-07 14:49:08] viktor at zuiderkwast dot se

The same problem exists in C++, which also lacks the finally clause. The standard way to solve the
resource allocation problem in C++ is instead by using the RAII design pattern.

As noted in Wikipedia on RAII, "In this language, the only code that can be guaranteed to be
executed after an exception is thrown are the destructors of objects residing on the stack.".
The same is valid for PHP (although the objects are reference-counted instead of being allocated on
the stack). The destructor is guarranteed to be called as soon as all references to the object run
out of scope, so the RAII is effectively usable in PHP.

So, the code you would put in the finally clause in Java etc has to be put in a destructor of some
object instead. Then, when a return or a or an uncatched exception occurs inside a try block, and
there are no other references to the object, the destructor will be called at this point to free the
resources.

In my optinion, the finally clause is a more elegant solution, although it might be *too
sophisticated* for PHP...

------------------------------------------------------------------------
[2011-07-25 03:27:14] ninzya at inbox dot lv

++finally

------------------------------------------------------------------------
[2011-07-22 07:53:27] dsberliner at gmail dot com

++ for finally in exception handling. Please reconsider.

------------------------------------------------------------------------
[2011-05-30 02:53:58] bat at flurf dot net

Here's an idea! Find all the people who think "finally" isn't needed in PHP. 
Invite them to go back to programming Visual Basic, because they're ignorant.  The rest can
work on implementing it.  Easy!

------------------------------------------------------------------------
[2011-05-05 11:52:26] ealexs at gmail dot com

PHP++ for finally in PHP ;)

my code:

disableSIPTrunk (10 lines of code)

try
{
    // do some stuff 
}
finally 
{
    enableSIPTrunk (10 lines of code)
}

// saves duplicate code and it's very elegant !

------------------------------------------------------------------------


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the rest of the comments, please view the bug report online at

    https://bugs.php.net/bug.php?id=32100


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