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From: Mel <mwilson@the-wire.com>
Newsgroups: comp.lang.python
Subject: Re: Feature suggestion -- return if true
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Date: Tue, 12 Apr 2011 11:12:09 -0400
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Paul Rubin wrote:

> zildjohn01 <zildjohn01@gmail.com> writes:
>>     _temp = expr
>>     if _temp: return _temp
> 
> I'm trying to figure out a context where you'd even want that, and I'm
> thinking that maybe it's some version of a repeat-until loop?  Python
> doesn't have repeat-until and it's been proposed a few times.

I can imagine

    return? tree_node.left
    return? tree_node.right

although my real code would probably be more like

    if tree_node.left is not None:
        return "left", tree_node.left
    if tree_node.right is not None:
        return "right", tree_node.right

where adding the "left" and "right" markers makes the return? feature 
impossible to use.

The proposed feature reminds me of the `zod` function (was that the actual 
name?) that returned 0 rather than bringing on a ZeroDivideError.  It would 
cement a strange corner-case into the language.

	Mel.