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Date: Tue, 4 Sep 2012 18:09:21 -0600
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To: Adam Jon Richardson <adamjonr@gmail.com>
Cc: internals@lists.php.net
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Subject: Re: [PHP-DEV] Moving to an AST-based parsing/compilation process
From: morrison.levi@gmail.com (Levi Morrison)

On Tue, Sep 4, 2012 at 4:20 PM, Adam Jon Richardson <adamjonr@gmail.com> wrote:
>
> However, as Knuth has said, "It is often a mistake to make a priori
> judgments about what parts of a program really critical, since the
> universal experience of programmers who have been using measurement
> tools has been that their intuitive guesses fail."
>
> So, I'm cautious about the premise that this will/could lead to an
> overall improvement in performance compared to the current
> implementation, a caution that the RFC spoke to very clearly.


This is probably why the section in the RFC is so small . . . :)

---

It seems to me to be a very wise decision to use an AST but good
decisions carried out poorly can be more harmful than helpful. We need
to do this correctly.  I hope this discussion will be helpful in this
regard.