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shape of time can get strange

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…and that’s what I want to show you today. …go to this URL…

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I do want to take a moment before we begin to ask you to participate in the spirit of the thing.

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bit.ly/nv-clobber

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This is the full state of our shared text editor. just a global string variable a text file is just a string

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I'm using a library called socket.io to handle networking between the browser and the server, because this talk isn't about networking. - simplest thing I could think of

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bit.ly/nv-quill

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bit.ly/nv-univax OK, obviously this works great, but it's not perfect. Let's say we want to collaborate and I'm in London… speed of light

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…This approach is solid, but it hardcodes network latency right into the app. And it's at this point that I get a little frustrated. Why is this so hard?

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All we want to do is edit a text file.

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This should be easy.

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Instead we keep failing. Just one approach after another stinks,

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and the kids are starting to ask their mother, "Why is daddy so angry all the time?"

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We could keep trying things, … So here's my question for you.

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(discuss before next slide)

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if you work on web sites long enough… I picked text editing because it's little,…

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… the speed of light? It is just a fact of life … How do we rephrase this requirement as something possible?

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And at the end we'll see if I ever actually got my collaborative text editor working, but for now we're going to set that aside …

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It's a kind of value that a computer knows how to deal with…

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String Number Array

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String Number Array text number sequence of values

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String Number Array text number sequence of values +, slice, replace, etc. +, -, *, Math.sqrt(), etc. arr[i], push, sort, etc.

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100% desirable… And that's all a CRDT is… example in a second. data type + ops over network + rules for conflicts …would solve our problem?

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String Now, a plain old string is not a CRDT. (why) But! … takes space … general pattern … add bookkeeping … not just text … history because conflicts.

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String +=

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This paper is only five years old.

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You can see … same things I’ve been talking about … … rethinking the fundamentals of programming and even of how we think about time … 14th example in this paper …

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Their implementation is 38 lines of pseudocode. It took me about 200 lines of JS.

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You would want to optimize.

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bit.ly/nv-peeredit

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github.com/jorendorff/peeredit