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Date: Wed, 01 Sep 2004 21:04:03 +0800
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Subject: parse errors when testing for undefined exceptions
From: alan@akbkhome.com (Alan Knowles)

This is a simple example of why making a parse error out of undefined 
Exception types is going to be very problematic.

function test($a) {

    if (!extension_exists('sqlite')) {
        return;
    }
    try {
        SQLite::query($a);
        
    // parse error!!! - if we dont have sqlite, we dont have SQLite 
exception!

    } catch(SQLite_Exception $e) {

        echo "problem with query";
        return;
    }
}


This has a big knock on effect that we can not lazy load Exception 
definitions, even if they are only used in Exceptional situations. (its 
pretty much the same issue as instanceof - forcing the loading of code, 
that may never be used, except to test it's non-existance.)

Regards
Alan