Question

Having a list of equally sized lists, e.g.:

(def d [["A" "B"] ["A" "C"] ["H" "M"]])

How can it be transformed into a list of sets, each set for the indexes above:

[#{"A" "H"} #{"B" "C" "M"}]

Answer 1

(map set (apply map vector d))

“(apply map vector)” is what is called “zip” in other languages like Python. It calls vector on the first item of each element of d, then the second item of each element, etc.

Then we call set on each of those collections.