> For the complete documentation index, see [llms.txt](https://xylo-lang.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://xylo-lang.gitbook.io/docs/builtin-functions/list.md). # List ### List Operators #### range from to Generates a list of all numbers between `from` (inclusive) and `to` (exclusive). List elements can be integer or float types. Equivalent to the `(..)` binary operator. Example: ```ocaml one_two_three = range 1 4 one_two_three = (..) 1 4 one_two_three = 1 .. 4 ``` #### rangei from to Returns a list of all numbers between `from` (inclusive) and `to` (inclusive). List elements can be integer or float types. Equivalent to the `(..=)` binary operator. Example: ```ocaml one_two_three = rangei 1 3 one_two_three = (..=) 1 3 one_two_three = 1 ..= 3 ``` #### concat x y Returns a list of length 2 containing `x` as the first element and `y` as the second element. `x` and `y` must be of the same type. Equivalent to the `(++)` binary operator. Example: ```ocaml one_two = concat 1 2 one_two = (++) 1 2 one_two = 1 ++ 2 ``` #### prepend value list Return a new list with `value` added to the start of `list`. `value` must be the same type as the elements of `list`. Equivalent to the `(+>)` binary operator. Example: ```ocaml one_two_three = prepend 1 [2, 3] one_two_three = (+>) 1 [2, 3] one_two_three = 1 +> [2, 3] ``` #### append list value Return a new list with `value` added to the end of `list`. `value` must be the same type as the elements of `list`. Equivalent to the `(<+)` binary operator. Example: ```ocaml one_two_three = append [1, 2] 3 one_two_three = (<+) [1, 2] 3 one_two_three = [1, 2] <+ 3 ``` ### Query Functions #### nth index list Returns the element at `index` of `list`. `index` must be of the integer type. Example: ```ocaml two = nth 1 [1, 2, 3] ``` #### length list Returns the number of elements in `list`. Example: ```ocaml three = length [1, 2, 3] ``` #### is\_empty list Returns true if length of `list` is zero, false otherwise. Example: ```ocaml true_ = is_empty [] ``` #### contains value list Returns true if `value` is equal to an element in `list`, false otherwise. Example: ```ocaml true_ = contains 3 [1, 2, 3] ``` #### index\_of value list Returns the index of first element in `list` that is equal to `value`, -1 if not found. Example: ```ocaml one = index_of 2 [1, 2, 3, 2] ``` ### Modification Functions #### set index value list Returns a new list where element of `list` at `index` is replaced with `value`. `index` must be of the integer type and `value` must be the same type as elements of `list`. Example: ```ocaml one_two_three = set 1 2 [1, 3, 3] ``` #### head list Returns the first element of `list`. Example: ```ocaml one = head [1, 2, 3] ``` #### tail list Returns a new list containing all elements of `list` except the first one. Example: ```ocaml two_three = tail [1, 2, 3] ``` #### init list Returns a new list containing all elements of `list` except the last one. Example: ```ocaml one_two = init [1, 2, 3] ``` #### last list Returns the last element of `list`. Example: ```ocaml three = last [1, 2, 3] ``` #### take count list Returns a new list containing the first `count` elements of `list`, or the last elements if `count` is negative. `count` must be of the integer type. Example: ```ocaml one_two_three = take 3 [1, 2, 3, 4, 5] three_four_five = take -3 [1, 2, 3, 4, 5] ``` #### drop count list Returns a new list excluding the first `count` elements of `list`, or the last elements if `count` is negative. `count` must be of the integer type. Example: ```ocaml three_four_five = drop 2 [1, 2, 3, 4, 5] one_two_three = drop -2 [1, 2, 3, 4, 5] ``` #### slice start end list Returns a new list containing elements from `list` between the `start` and `end` indices. `start` and `end` must be of the integer type. Example: ```ocaml two_three = slice 1 3 [1, 2, 3, 4, 5] ``` #### split index list Divides `list` into two parts at `index`, returning a two-dimensional list containing the two resulting sublists. `index` must be of the integer type. Example: ```ocaml true_ = [[1, 2], [3, 4]] == split 2 [1, 2, 3, 4] ``` ### Transformation Functions #### reverse list Returns a new list with the elements of `list` in reverse order. Example: ```ocaml three_two_one = reverse [1, 2, 3] ``` #### unique list Returns a new list containing only the distinct elements of `list`, removing duplicates. Example: ```ocaml one_two_three = unique [1, 2, 1, 2, 3, 3, 3] ``` #### sort list Returns a new list with the elements of `list` sorted in ascending order. Example: ```ocaml one_two_three = sort [1, 3, 2] ``` #### flatten list Returns a new list by concatenating all nested lists within `list` into a single, one-dimensional list. Example: ```ocaml one_two_three = flatten [[1, 2], [3]] ``` #### intersperse value list Returns a new list with a specified value inserted between each element of `list`. `value` must be of the same type of the elements of `list`. Example: ```ocaml one_four_two_four_three = intersperse 4 [1, 2, 3] ``` ### Reduction Functions #### min\_of list Returns the smallest element of `list`. Elements of `list` must be of the integer or float types. Example: ```ocaml one = min_of [2, 1, 3] ``` #### max\_of list Returns the largest element of `list`. Elements of `list` must be of the integer or float types. Example: ```ocaml three = max_of [1, 3, 2] ``` #### sum list Returns the total sum of all elements in `list`. Elements of `list` must be of the integer, float, or complex types. Example: ```ocaml ten = sum [1, 2, 3, 4] ``` #### product list Returns the total product of all elements in `list`. Elements of `list` must be of the integer, float, or complex types. Example: ```ocaml twenty_four = product [1, 2, 3, 4] ``` --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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