Hello, is it possible to replace a function node containing the following code, with a change node? var metric = global.get('metric'); metric++; global.set('metric', metric);

[image] E1cid: globalContext Amazing! Where in the docs would you find that precious little gem?

[image] duaw: Amazing! Where in the docs would you find that precious little gem? IT HELPS TO READ THE DOCUMENTATION: https://nodered.org/docs/user-guide/context

Of course, I do read the docs and I use that valuable information mentioned there. However, this JSONata magic [image] E1cid: JSONata expression $globalContext("metric") + 1 was new to me! I read and re-read that piece of documentation, but I cannot find that JSONata magic! (Or do I miss s…

Also if you look at the Jsonata expression editor all $functions are listed there, with their parameters.

In case you did not realise, JSONata is just a tool that is included in node-red. If you want a full explanation you need to look in the JSONata documentation.

I agree, that a complete Jsonata re-documentation would be out of scope for Node-RED. IMHO I would like to see the example above, how Jsonata can interact with messages, or context inside the Cookbook ( https://cookbook.nodered.org/ ). It would be a good starting point to allude users to this powerful…

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Increment a global variable with a change node

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E1cid 28 April 2021 20:53 2

Yes that's possible'
Set Global metric
JSONata expression
$globalContext("metric") + 1

Add an var with memory var

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Increment a global variable with a change node

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