title: How does one compile single file Xcode 4?
body: <p>While I used to compile a single source file with <kbd>Cmd</kbd>+<kbd>K</kbd> in prior versions of Xcode, how does one do the same in Xcode 4? (Note that this is different than preprocessing or showing the disassembly of the file.) If compiling from a command line is proposed then it must be such that the project's settings, include paths, preprocessor definitions, etc., are all included.</p>
  
  <p>An example use case is where I make a header file change but only want to test the change's effect with respect to a single source file, not all of the files that depend upon that header.</p>