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Message from discussion Generalizing -> & ->>
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Laurent PETIT  
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 More options Nov 13 2009, 1:27 am
From: Laurent PETIT <laurent.pe...@gmail.com>
Date: Fri, 13 Nov 2009 07:27:49 +0100
Local: Fri, Nov 13 2009 1:27 am
Subject: Re: Generalizing -> & ->>
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Oh yes, thanks for refreshing my memory.
And indeed it makes sense to place the question mark in the "questioned" side :)

2009/11/13 Wilson MacGyver <wmacgy...@gmail.com>:

> Yes, it's groovy, and it's "?." It's called safe navigation operator

> http://groovy.codehaus.org/Operators#Operators-SafeNavigationOperator...

> On Thu, Nov 12, 2009 at 6:03 PM, Laurent PETIT <laurent.pe...@gmail.com> wrote:
>> 2009/11/3 Alex Osborne <a...@meshy.org>:

>>> Sean Devlin wrote:
>>>> This is slightly unrealted, but how does one pronounce ->, ->> and the
>>>> like?  Is this documented?

>>> The doc-strings usually give you a nice hint.  I usually use "thread"
>>> for -> and "thread last" for ->>.  The actual symbols I think of as
>>> "arrow" and "double arrow".

>>> Then -?> in contrib is "short-circuiting thread".  Not sure about the
>>> symbol, perhaps "questionable arrow"? ;-)

>> The question mark ? is there to "mimic" (somewhat) what one can find
>> in OO languages such as groovy (I think it's groovy, is it ?) :

>> someObject.?propA.?prop2

>> where .? will check if the object is null before trying to get a
>> property (or method) on it. If null : returns null, if not null,
>> returns the property etc.

>> Initially i wanted to name it ->? but the final ? is by convention
>> reserved for predicates, so Rich suggested -?> (and also .?. for the
>> .. equivalent).

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