# JSONata array lookup using msg property

**URL:** <https://discourse.nodered.org/t/jsonata-array-lookup-using-msg-property/53637>\
**Category:** General\
**Created:** [12 November 2021 14:12 UTC](https://discourse.nodered.org/t/jsonata-array-lookup-using-msg-property/53637 "2021-11-12T14:12:52Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![cymplecy](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/cymplecy/32/2773_2.png) [@cymplecy](https://discourse.nodered.org/u/cymplecy)\
**Post date:** [12 November 2021 14:12 UTC](https://discourse.nodered.org/t/jsonata-array-lookup-using-msg-property/53637/1 "2021-11-12T14:12:52Z")

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The trouble I have using JSONata once a year is that I can never work out the syntax required

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/a/d/adbcb5bcead42d12a1c215ee691de9aa7f90638f.png)

msg.random contains number 0..2

How can I pick out the corresponding colour from the array?

Currently getting undefined

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**Author:** ![E1cid](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/e1cid/32/77971_2.png) [@E1cid](https://discourse.nodered.org/u/E1cid)\
**Post date:** [12 November 2021 14:18 UTC](https://discourse.nodered.org/t/jsonata-array-lookup-using-msg-property/53637/2 "2021-11-12T14:18:06Z")

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Try `[1,2,3][$$.random]`

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**Author:** ![cymplecy](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/cymplecy/32/2773_2.png) [@cymplecy](https://discourse.nodered.org/u/cymplecy)\
**Post date:** [12 November 2021 14:20 UTC](https://discourse.nodered.org/t/jsonata-array-lookup-using-msg-property/53637/3 "2021-11-12T14:20:21Z")

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Thank you  
 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/4/a/4afbdf1079e9ef28b57d81fe817a1e9c82cb887a.png)

I MUST TRY TO REMEMBER ABOUT $$. !!!!

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**Author:** ![E1cid](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/e1cid/32/77971_2.png) [@E1cid](https://discourse.nodered.org/u/E1cid)\
**Post date:** [12 November 2021 14:21 UTC](https://discourse.nodered.org/t/jsonata-array-lookup-using-msg-property/53637/4 "2021-11-12T14:21:24Z")

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I have taken to using $$ when referencing msg properties, as a fail safe to what ever scope the expression is in.

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**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [26 November 2021 14:22 UTC](https://discourse.nodered.org/t/jsonata-array-lookup-using-msg-property/53637/5 "2021-11-26T14:22:06Z")

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