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To: "Stas Malyshev" <smalyshev@sugarcrm.com>,
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Date: Thu, 9 Aug 2012 08:33:01 +0300
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Subject: Re: [PHP-DEV] Error handling brainstorming
From: sv_forums@fmethod.com ("Stan Vass")

> Hi!
>
>> Because checking that the returned variable is `!== FALSE` is *way*
>> better than throwing an exception, right?
>
> Yes, it is. You can control it, unlike the exception which you can not,
> unless, again, you wrap everything into try/catch on every kind of
> exception possible.

Have you stopped for a moment to think this opinion through? Look at two 
typical patterns of error handling. The examples below are generalized from 
my file cache code. Having no cache is exceptional, because 99.999% of the 
time I run this, there is cache, except the first time when there's not.

Tell me again how you using try..catch is very verbose and how you need to 
supply multiple catch blocks for "every kind of exception possible"?

With exceptions:
----------------
try {
    fileop1();
    fileop2();
    fileop3();
    normal_actions();
} catch (IOException $e) {
    exceptional_actions();
}

Without exceptions:
--------------------
$valid = true;
if (fileop1() !== FALSE) {
    $valid = false;
}

if ($valid && fileop2() !== FALSE) {
    $valid = false;
}

if ($valid  && fileop3() !== FALSE) {
    $valid = false;
}

if ($valid) {
    normal_actions();
} else {
    exceptional_actions();
}