How to "Version" Your Xcode Code

Sometimes I did some mistake. After that I made some bug and f开发者_运维知识库or some reason the program won't run. I want to go back to previous version. How would I do that?

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In xCode 4 you can create a local git repository on creating a project. Look here. If you are not using xCode 4, you can use external tools for git or svn. Just google for it, you will find a lot of solutions!

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You need to use a revision control system. This is a big topic, so start by reading the Wikipedia page.

Xcode has support for a few revision control systems. This question discusses most of them, but git support wasn't available back then (although, personally, I have an irrational hatred of git).