pop for a set - is there something prettier?

[HJarausch]

Thanks for all these comments. If I have a set _S_ I can say 
    
    
    for e in S :
      echo e
    
    
    Run

Does Nim construct an iterator of S like _items(S)_ [which doesn't work] ? If 
yes, how is it called - one could assign via let and call it once to an element 
of a set.