Question

Still working on lisp recipes and idioms.

I have a list like this:

((a b c) (d e f) nil (g h))

I’d like to consolidate that to one list,

(a b c d e f g h)

Seems like there oughta be a one-liner for that.

Answer 1

(apply #'append '((a b c) (d e f) (g h i)))

or

(loop for outer in '((a b c) (d e f) (g h i))
      nconcing (loop for inner in outer collecting inner))