The pedantic answer is the code block following the for is not parsed as or represented as a code block internally. You don't need the "do" but Ruby slurps it u

The pedantic answer is the code block following the for is not parsed as or represented as a code block internally. You don't need the "do" but Ruby slurps it up to play nice. Only block semantics were fixed, but those for constructs like while, until, for, or loop remain the same as they do not introduce new scope.