   ## a comment

\## not a comment

#if foo
  ${bar}
#endif

The answer is:
#choose
  #when 0 == 1
    0
  #end
  #when 1 == 1
    1
  #end
  #otherwise
    2
  #end
#end -- comment about choose

#for item in items
  * ${item}
#end

#def greeting(name)
  Hello, ${name}!
#end
${greeting('world')}

#with y=7; z=x+10
  $x $y $z
#end
