-
Thank you for the suggestion . That’s an elegant solution.
I’m struggling to understand it though. Could you please help explain the following?
q) reverse sums 1 2 3 6 3 1 / This makes sense. q) (reverse sums) 1 2 3 1 3 6 / Why did we lose the reverse? q) (reverse sums::) 1 2 3 6 3 1 / Why did this recover the reverse? q) q) sums + / Makes sense. q) reverse |: / Reverse is a combination of the max and assignment operators? q) reverse sums + / Reverse was lost. q) reverse sums:: |+ / Max operator combined with sums?
I suspect the issue is I don’t understand the meaning of | and ::. I had thought | was just the max operator but maybe is also has other meanings? I know :: has at least these meanings:
- Defining a view.
- Assignment in-place.
- Assignment to a global variable.
- The generic null.
- The identity function.
- An elided index used to select everything.
Does :: have yet another meaning here or does one of the above apply?