Moving an Xcode project from Objective-C to MacRuby can be useful as a way to create a MacRuby example. The Xcode distribution, in particular, contains dozens of example projects which could serve as starting points. One might also wish to convert a real-world application in order to benefit from MacRuby's flexibility, assorted Ruby libraries, etc.
However, performing such a conversion in a single step is risky, because multiple translation errors may conspire to complicate debugging. Fortunately, it is possible to move projects in an incremental manner.
Make a copy of an existing project.
Modify the copy to link against the !MacRuby framework.
main.mfrom an existing !MacRuby application (change).
rb_main.rbfrom an existing !MacRuby application (addition).
*.rbinto the Resource directory of the application bundle.
SomeClass.rb, corresponding to
SomeClass.rb, define a replacement method (and class, if need be).