Aargh, all these re-implemented text editors on the web. :/
Any chance you'll be adding this source code to GitHub?
Etherpad is optimized for text, while Ace (the editing widget CodeShare.io uses) is built for code. It has syntax highlighting, folding, automatic indentation, etc.
It looks like Etherpad Lite may be using Ace, but I don't immediately see a way to turn on the nice programmer-y features.
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