# Question about Javascript pattern

**URL:** <https://forums.kodeco.com/t/question-about-javascript-pattern/13513>\
**Category:** tvOS Apprentice\
**Created:** [April 17, 2016, 4:09am UTC](https://forums.kodeco.com/t/question-about-javascript-pattern/13513 "2016-04-17T04:09:14Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![momenteye](https://assets.chunter.kodeco.com/user_avatar/forums.kodeco.com/momenteye/32/110937_2.png) [@momenteye](https://forums.kodeco.com/u/momenteye)\
**Post date:** [April 17, 2016, 4:09am UTC](https://forums.kodeco.com/t/question-about-javascript-pattern/13513/1 "2016-04-17T04:09:14Z")

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Page 66

> getDocument(name, data) {  
> data = data || {};  
> …  
> }

What is function the pattern “data = data || {};”  
So far as I can see it will evaluate to true.  
Is it a way of checking that data has a value?

Thanks

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**Author:** ![aeberbach](https://assets.chunter.kodeco.com/user_avatar/forums.kodeco.com/aeberbach/32/81494_2.png) [@aeberbach](https://forums.kodeco.com/u/aeberbach)\
**Post date:** [April 18, 2016, 2:02am UTC](https://forums.kodeco.com/t/question-about-javascript-pattern/13513/2 "2016-04-18T02:02:17Z")

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In this case it is a coalescing operator. It checks that data is something valid and if not it is initialised as an empty object {}.

It is shorthand for `data = (data != nil ? data : {})`