I am not sure where to report this. When using the Monaco editor this code, in a function node, generates an error. const d1 = new Date() const d2 = new Date(d1.getTime() + 1000) msg.payload = d2 - d1 return msg; Hovering over d2 in the third line shows: [image]

I've noticed such issues occasionally in VScode as well. If you really want to get rid of it, you can force the type checker: const d1 = /** @type {number} */ (new Date()) const d2 = /** @type {number} */ (new Date(d1.getTime() + 1000)) msg.payload = d2 - d1 return msg; Note the brackets round th…

In simple terms, It's something to do with type definitions and what is supported by the subtract operator. Typically objects don't know how to be added/subtracted from one another however some objects (like Date) have a prototype named valueOf that is automatically executed by the V8 engine (under …

@TotallyInformation @Steve-Mcl , yes there are easy workarounds, I was just reporting it in case it is something that should be looked at.

[image] Colin: new Date() I found swapping for Date.now() solved the error.

Yup, that would also do it! So that is at least 5 ways - gotta wonder about JavaScript sometimes!

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Monaco editor does not allow subraction of dates

General

Steve-Mcl 2 November 2021 21:40 7

And soon to be 6 with Temporal

2 Likes

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Monaco editor does not allow subraction of dates

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