A friend of mine suggested that I learn Swift, as it would help me get a job that I had applied for, and I thought this was a good idea. The only problem: I don't own a Mac computer, or anything with OS X. Is there any way I can try programming on Swift in a non-OS X environment, like Windows or iOS? Any help would be appreciated. I don't want to have to buy another computer just to learn a language.
Currently Swift is not available except through Apple's Developer program as part of the Xcode 6 Beta. Rumors seem to suggest that Swift will not be available elsewhere until the beta is finished.
If you want to use Swift now, your only option is to emulate/virtualize OS X and run Xcode 6. I do not know the legalities of doing this.
However, when Swift is formally released, I would assume/hope that it will be simply a part of LLVM. If this does happen, then you will be able to use Swift on any platform via LLVM.
The Swift API, however, will still exist exclusively on OS X for a while afterwards until someone re-implements it for other platforms.
Swift has now been open sourced. From swift.org
On December 3, 2015, the Swift language, supporting libraries, debugger, and package manager were published under the Apache 2.0 license with a Runtime Library Exception, and Swift.org was created to host the project. The source code is hosted on GitHub
Swift has been ported to OSX and Linux. The Ubuntu compiled version is here.