Elixir - Passing multiple lists as function parameters -

i new in elixir google searches , reading have not found me solution current problem. have seen examples in books , tutorials passing in single list parameter function so: [ head|tail ].

defmodule math   def double_each([head|tail])     [head * 2| double_each(tail)]   end    def double_each([])     []   end end 

i need pass in 2 lists , perform actions on them, so:

defmodule pagination   def getpaginatedlist([], _, _, _)     []   end    def getpaginatedlist([list], [paginated], f, l) when f == 1     enum.take(list, l)   end    def getpaginatedlist(_, [paginated], f, l) when l <= f     paginated   end    def getpaginatedlist([list], [paginated] \\ [], f, l)     getpaginatedlist(tl(list), paginated ++ hd(list), f, l - 1)   end end 

however, receive error function clause not matching when passing in list , list b in error below:

iex(23)> pagination.getpaginatedlist(a, b, 1, 2) ** (functionclauseerror) no function clause matching in pagination.getpaginatedlist/4 pagination.ex:2: pagination.getpaginatedlist([1, 2, 3, 4, 5], [], 1, 2)

any ideas on may doing incorrectly? (apologies if simple question answer. have not been able find answer after few hours of searching , playing around this.)

your issues list argument pattern match. list , paginated arguments, don't need wrap them in list, since you'd matching on nested list. also, it's conventional use snake case in elixir function names. try giving shot:

defmodule pagination   def get_paginated_list([], _, _, _)     []   end    def get_paginated_list(list, paginated, f, l) when f == 1     enum.take(list, l)   end    def get_paginated_list(_, paginated, f, l) when l <= f     paginated   end    def get_paginated_list(list, paginated \\ [], f, l)     get_paginated_list(tl(list), paginated ++ hd(list), f, l - 1)   end end