Problem: character subsets

Code: character+subsets/tails_1642268953

Nibbles version: 0.2 | 0.21 | 0.22 | 0.23 | 0.24 | 0.25 | 1.00

Format: Compact | Simple | +Type | Table | JSON | .nbl (DeBruijn) | .nbl (names)

(implicit map):[[chr]] 
    `* (nary cartesian product):[[chr]] 
        . (map):[[chr]] 
            `$ (uniq):[chr] 
                @ (= fstLine):[chr] 
            : (append):[chr] <--arg( A:chr ) 
                "\n" (string):[chr] 
                $ (= A):chr 
    | (filter):[chr] <--arg( C:[chr] B:[chr] ) 
        (implicit arg = C):[chr] 
        (implicit arg = D):chr <--arg( D:chr )