- element: "Þf"
  name: Flatten to depth
  description: Flatten a list to a certain depth (default 1)
  arity: 2
  overloads:
    lst-num: flatten a to depth b
    any-lst: Flatten b to depth 1, push a as well
  vectorise: false
  tests:
    - "[[[[[[1]]]]],3] : [[1]]"
    - '["xyz",[1,2,[3,4,[5,6]]]] : [1,2,3,4,[5,6]]'

def flatten(argument,d):
	flat = []
	if(d==0):
		return argument
	if type(argument) == list:
		for item in argument:
			flat += flatten(item, d-1)
	else:
		flat.append(argument)
	return flat