This commit improves the interface by which a DO/NEXT is done. Before, each DO/NEXT would return the evaluative result (like DO) but allow the updated position to be stored in a variable: >> do/next [1 + 2 10 + 20] 'pos == 3 >> pos == [10 + 20] This changes that to return the new position and optionally update a variable with the output result. Since this changes the contrac…
