From dmercer@REDACTED  Tue May  1 04:20:51 2012
From: dmercer@REDACTED (David Mercer)
Date: Mon, 30 Apr 2012 21:20:51 -0500
Subject: [eeps] EEP XXX: Pattern-test operator
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On Apr 30, 2012, at 1:52, "Richard O'Keefe" <ok@REDACTED> wrote:

> 
> On 30/04/2012, at 1:59 PM, David Mercer wrote:
>> You actually answered that quite well, and I understood your answer.  I was just trying to understand *why* or *when* binding in guards might be necessary.
> 
> That's described in Erik S?e S?rensen's original proposal.
> 
> Here's an example, adapted from one of his.
. . .
> Following this example, you will see that it is easy to come
> up with examples that take O(n) tokens to write using ?= but
> O(n**2) without.  

Thanks, ROK.  Excellent explanation.

Cheers,

DBM