flatten
builtin-function
(flatten seq &optional (depth int32:MAX-VALUE))
Returns a lazy sequence with subsequences replaced by their elements up to a certain depth.
make-html > (flatten '(a (b c (d e) f)))
it: (a b c d e f)
make-html > (flatten '(a (b c (d e) f)) 1)
it: (a b c (d e) f)