Hello,

thank you for creating this pull request. I have automatically opened an issue
on our Jira Bug Tracker for you. See the issue link:

http://www.doctrine-project.org/jira/browse/DBAL-926

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There is no advantage in porting a PSR-0 compliant library to PSR-4. Please don't change it unless there's an advantage in doing so.

Advantage is it's faster

I would rather ask what's the disadvantage of using PSR-4 in composer?

@Tobion it's not faster. For production purposes, you are supposed to use composer dump-autoload --optimize. Note that doctrine project also voted against PSR-4 in FIG.

Why would it not be faster in development? It's just as important. It removes the logic to load PEAR-like classes in this repo. So it's definitely faster. Again, what's the disadvantage? I don't see it.

That's not I/O - the performance impact is negligible