How to solve the `TypeError: Attempted to assign to readonly property` error
I was doing something in my Next.js codebase when I ran into this problem:
TypeError: Attempted to assign to readonly property
Weird! After a bit of debugging I found the problem. I has nothing to do with Next.js, it can happen in any JavaScript codebase.
I had a column in my database where I stored data as JSON.
In my code I was updating this JSON object, using the dot syntax (like data.name = 'Flavio') but I forgot to call JSON.parse() before doing so.
data was not an object, but a string!
Strings are immutable in JavaScript. We can’t update them once defined. Hence the error. The solution was to, obviously, call JSON.parse() before updating the JSON object.
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