I have been using node red for quite a while and have run into an issue I have never seen. I am pulling in an array from a server and saving it as a global variable using a change node. This works as expected, the array saves as the variable. However it is being overwritten for some reason in a f…

Javascript uses references for objects, so when you set BT to the global you set a reference to the global. Then when you alter BT you you also change the global that it references. best to clone the global object BT = RED.util.cloneMessage(global.get("BackTestSMA21")) https://nodered.org/docs/ap…

Thank you for the input, it is definitely happening in this function block, I was able to narrow it down to this function block, I don't even reference the main array global anywhere else, and did a quick test of disabling this function block to prove it out. It's super weird behavior I've never ha…

[image] jaugs: Function block with the following code: BT = global.get("BackTestSMA21") Test = msg.payload; c = Test.c.slice(0,BT); v = Test.v.slice(0,BT); return msg Are you certain that is the full function code? It doesn't do anything at all. You grab a global "thing" then make 2 s…

I am doing more with that function block, but even just that little bit appeared to change the global that was being fed in. BT = global.get("BackTestSMA21") Test = msg.payload; c = Test.c.slice(0,BT); h = Test.h.slice(0,BT); l = Test.l.slice(0,BT); o = Test.o.slice(0,BT); sma = Test.sma.slic…

[ { "id": "95283eaf.abcaf", "type": "inject", "z": "3e144ca1.3f13a4", "name": "", "props": [ { "p": "payload" }, { "p": "topic", "vt": "str" } ], …

Here is a sample flow using that smaller object from above that looks to be behaving the same, writing over the mainArray global

[image] jaugs: There may be a much easier way of accomplishing this, I am just confused why this function block would ever overwrite that first global. As I suspected, there was more to your function than that little bit of code you provided in the first post. What's happening is when you (i…

Wow, learning something new everyday. Thanks for your help y'all!

Global Variable being overwritten without global.set

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system Closed 20 May 2021 00:19 10

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Global Variable being overwritten without global.set

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