Ordered iterators

Currently there is no way to express ordered iteration in DAX. This makes it impossible (or practically impossible) to calculate values where order matters. For example, I would like to be able to use DAX to calculate a final price after a set of discounts. These discounts can either be fixed dollar discounts or % of the previous price but the order in which they are applied matters and is not uniform. Case 1: Original Price: $10 1. Discount: 50% 2. Discount: $2 Final Price: (10 * .5) - 2 = $3 Case 2: Original Price: $10 1. Discount: $2   2. Discount: 50% Final Price: (10 - 2) * .5 = $4 My data source supplies the order of the discounts, but there could be arbitrarily many of them and no set order between $ and % discounts. To solve this I propose to add the following to DAX: SORT(, ) ORDEREDX(, ) ADDORDEREDCOLUMNS(, , [, , ]) PREVIOUS(, ) where in ORDEREDX or ADDORDEREDCOLUMNS can contain PREVIOUS which is the value calculated from the previous row iteration and has if the previous expression doesn't exist. is a list of columns and the order in which to sort them. My calculation could then be: ORDEREDX(SORT(Discounts, {{"DiscountOrder", ASC}}), IF(Discounts[Type] = "%", PREVIOUS(SUM(Prices[Price]), 1) * Discounts[Discount Value], PREVIOUS(SUM(Prices[Price]), 1) - Discounts[Discount Value]) These additions coincide well with the visual language additions proposed in https://ideas.powerbi.com/forums/265200-power-bi-ideas/suggestions/40487983-dax-calculations-at-visual-level-of-reports