explicit output

closes #4316

Author: coke

doc/Language/variables.rakudoc

@@ -760,7 +760,7 @@ This works per "clone" of the containing code object, as in this
 example:
 
 =for code
-({ state $i = 1; $i++.say; } xx 3).map: {$_(), $_()}; # says 1 then 2 thrice
+({ state $i = 1; $i++.say; } xx 3).map: {$_(), $_()}; # OUTPUT: «1␤2␤1␤2␤1␤2␤»
 
 Note that this is B<not> a thread-safe construct when the same clone of
 the same block is run by multiple threads.  Also remember that methods