Editors created in Processing are capable of running several different computer languages; basically if there is a compiler for a language, a Processing editor app can run the source code for that language. The following is a MacOS only demonstration of this. It uses swiftc from the command line to compile .swift source code for an iOS app and then runs the code on a simulator provided by XCode (installation required). It also requires two .jar files: one for Info.plist creation and one for editor syntax highlighting. Details and source code are here: https://github.com/vsquared/iOSEditor_Processing
Output:
