I think first() exists so there is a semantic pair for functional programming: 
first()/head() and tail()  or init() and last()

________________________________
From: ocs@ocs <[email protected]>
Sent: Thursday, October 18, 2018 1:20 PM
To: [email protected]
Subject: Re: DGM for first or default

Well I thought first is smart enough to return null for an empty list, same as 
my firstObject in Cocoa does. If it throws, what's on earth point of having the 
thing at all? In that case it can be replaced by list[0] without any drawback 
at all.

All the best,
OC

On 18 Oct 2018, at 7:19 PM, Milles, Eric (TR Technology & Ops) 
<[email protected]<mailto:[email protected]>> wrote:

"list?.first() ?: defaultValue" is not the equivalent.  If the collection is 
empty, first() throws an IndexOutOfBoundsException is thrown.  That's why I'm 
asking if there is a simple equivalent.  I suppose this is the equivalent now 
that I think about it:

list ? list.first() : defaultValue


________________________________
From: ocs@ocs <[email protected]<mailto:[email protected]>>
Sent: Thursday, October 18, 2018 12:07 PM
To: [email protected]<mailto:[email protected]>
Subject: Re: DGM for first or default

Myself, I am not a huge fan of adding not-often-needed functionalities (and 
actually would add almost none of those discussed lately); nevertheless...

On 18 Oct 2018, at 6:48 PM, Paolo Di Tommaso 
<[email protected]<mailto:[email protected]>> wrote:

-1, it can be easily done as:
list.first() ?: defaultValue

... this won't work in case the first object is a Groovy False (e.g., an empty 
string, or a plethora of others).

All the best,
OC



p

On Thu, Oct 18, 2018 at 6:45 PM Daniel.Sun 
<[email protected]<mailto:[email protected]>> wrote:
+0 from me.
P.S. we should add similar DGM for `last` too?

Cheers,
Daniel.Sun




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Daniel Sun
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