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Comment by sonofhans | Hacker News Reader

This is nice.

I’m curious — it looks like you’re storing the full text string along with the timestamp. At first I thought you were capturing keystrokes, but it makes more sense to capture the full text, so you can allow people to edit with mouse/arrow keys, etc.

It will fall over at some point though, right? If you work on this more, is the next logical step to store a diff with each timestamp, rather than the full string?

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Thanks, this is an interesting point. Storing the full message indeed has a downside in terms of storage (but for a short text it should be unnoticeable). I guess it also brings something positive: you can select the whole text, delete it, and start again, and the whole action should be stored. Making a diff to represent this is way more complicated.

I'll still think about this though. I think I could find a way to reduce the data size for most use cases.

You can introduce multiple types of changes, for example: addition at the end, removal of N characters from the end, and complete string replacement, etc. Then for each change you can calculate which type is more efficient to store.

Yes, already working on it! Thanks!

That's what I was thinking as well. I loved the demo, but was a bit surprised at how much redundant data was stored behind the scenes.

Capturing keystrokes could still be a viable option if you maintained something like a virtual cursor that could move around the text display area.

Or of course, diffs are the most straightforward way to do it.

I changed the code to add a diff. Thanks for your input! (pun intended)

That was quick! It seems to work as well as ever. The data structure is less legible, but a lot more efficient.

Such a little project. I hope to find a use for it.

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