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From: Dennis Lee Bieber <wlfraed@ix.netcom.com>
Newsgroups: comp.lang.python
Subject: Re: The Cost of Dynamism (was Re: Pyhon 2.x or 3.x, which is faster?)
Date: Sat, 26 Mar 2016 13:45:13 -0400
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On Sat, 26 Mar 2016 03:22:58 +1100, Steven D'Aprano <steve@pearwood.info>
declaimed the following:


>(3) and the body of the for-loop has no side-effects that might affect the
>truth of (1)
>
	<snip>
>I don't have an intuition on how hard #3 (does the loop body have any
>side-effects that might affect this optimization?) might be, except to say
>that the presence of an eval or exec inside the body will probably make the
>optimization unsafe.
>
	Probably very difficult, if the loop is at top-level (making "i" a
module global), and if the loop body can call any function that might
declare "global i" within the same module.
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
    wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/