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From Mario Garcia <mario.g...@gmail.com>
Subject Re: DGM for first or default
Date Thu, 18 Oct 2018 17:52:40 GMT
Eric you can use `find`:

list.find() ?: defaultValue

The method find with no arguments takes the first element, and if the
collection is empty or null it will return null and you won't get an
IndexOutOfBounds

Regards
Mario

El jue., 18 oct. 2018 a las 19:32, Milles, Eric (TR Technology & Ops) (<
eric.milles@thomsonreuters.com>) escribió:

> Is it still valuable to have DGMs -- whether named "first()" or
> "firstOrDefault()" or whatever?  Content assist does not propose "list ?
> list.first() : defaultValue".  I suppose I'd need to create a code template
> to get that proposal in the IDE.
>
>
> Are there any other small idioms like this that anyone has added as a
> template to improve the editing experience?
> ------------------------------
> *From:* Milles, Eric (TR Technology & Ops)
> *Sent:* Thursday, October 18, 2018 12:19:42 PM
> *To:* dev@groovy.apache.org
> *Subject:* Re: DGM for first or default
>
>
> "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 <ocs@ocs.cz>
> *Sent:* Thursday, October 18, 2018 12:07 PM
> *To:* dev@groovy.apache.org
> *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 <paolo.ditommaso@gmail.com>
> 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 <sunlan@apache.org> wrote:
>
> +0 from me.
> P.S. we should add similar DGM for `last` too?
>
> Cheers,
> Daniel.Sun
>
>
>
>
> -----
> Daniel Sun
> Apache Groovy committer
> Blog: http://blog.sunlan.me
> <https://urldefense.proofpoint.com/v2/url?u=http-3A__blog.sunlan.me_&d=DwMFAg&c=4ZIZThykDLcoWk-GVjSLmy8-1Cr1I4FWIvbLFebwKgY&r=tPJuIuL_GkTEazjQW7vvl7mNWVGXn3yJD5LGBHYYHww&m=eCM29fHJoKqW_CdKJO2GxdVR6VMqldnDZ9NQgYxSo08&s=Kuqjwc4Pu38Y9C4Zooo3uBjDkGvyna3lloonS2m7GTE&e=>
> Twitter: @daniel_sun
>
> --
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