Loop Structures
    loop { ... };
    loop { ... } while EXPR;
    loop { ... } until EXPR;
    loop $i = 0; $i < 10; $i++ { ... }
    
    while EXPR { ... }
    until EXPR { ... }
    
For Loop structures
    for @foo { ... }
    for @foo -> $x { ... }
    for @foo -> $x, $y, $x { ... }
    for @foo.kv -> $index, $value { ... }
    
    for %hash.kv -> $key, $value { ... }
    
    for =<> {...} # was while (<>) { ... } in p5
    
Switch/Case style control elements
	given $x { ... }   # $x is now topic for block
	when EXPR { ... }  # perform $_ ~~ EXPR execute block and break
   default { ... }    # same as when true { ... }    
