anchor.diff:  needs to be added)
   
   .Rust build.rs Synopsis
  -[source,rust]
   -------------------------------------------------------------------------------
   use std::env;
   
  
positive.code: 
  The next mandatory step is of course to display the famous greeting:
  
  -------------------------------------------------------------------------------
  $ t2-output/macosx-gcc-debug-default/HelloWorld
  hello, world
  
negative.code: for the unit tests, which must be made available via the Git submodule
  mechanism:
  
  [source, sh]
  -------------------------------------------------------------------------------
  $ git submodule init
  $ git submodule update
  