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Discussion on: JavaScript clone and rewrite property from existing object

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jonrandy profile image
Jon Randy 🎖️ • • Edited

Eh? The easiest way to overwrite a property is just to set it on the object:

user.online = true
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Your examples are not overwriting the original object at all - they are creating a totally new object and overwriting the property on that. The original user object will remain unchanged

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dailydevtips1 profile image
Chris Bongers •

You are completely right Jon,

I forget to mention a context where you want to keep the original existing.
I use this method for updating states that don't need to refresh in the UI (React)

Could have probably worded it a bit differently

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peerreynders profile image
peerreynders •

I wonder if in this context "Rewriting JavaScript object properties" might be a better way of putting it.

Strangely enough "updating" an Elixir map

%{expenses | groceries: 150, commute: 75}
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or an Elm record

{ steve | name = "Wozniak" }
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creates an entirely new value as well (because everything is immutable).