set.to_list

Author: lpil

CHANGELOG.md

@@ -5,8 +5,8 @@
 - Created the `iterator` module with the `unfold`, `repeatedly`, `repeat`,
   `from_list`, `fold`, `run`, `to_list`, `take`, `drop`, `map`, `filter`,
   `cycle`, and `range` functions.
-- Created the `set` module with the `new`, `insert`, `delete`, and `contains`
-  functions.
+- Created the `set` module with the `new`, `insert`, `delete`, `to_list` and
+  `contains` functions.
 - Created the `io` module with the `print`, `println`, and `debug` functions.
 - Created the `queue` module with the `new`, `from_list`, `to_list`,
   `is_empty`, `length`, `push_back`, `push_front`, `pop_back`, `pop_front`,
@@ -26,6 +26,7 @@
   `tuple2_of` functions.
 - The `list` module gains the `filter_map` function.
 - The `list.contains` label `has` has been changed to `any`.
+- The `list.sort` label `sort_by` has been changed to `by`.
 
 ## v0.8.0 - 2020-04-28
 

src/gleam/list.gleam

@@ -721,10 +721,10 @@ fn do_sort(
 /// ## Examples
 ///
 ///    > import gleam/int
-///    > list.sort([4, 3, 6, 5, 4, 1, 2], int.compare)
+///    > list.sort([4, 3, 6, 5, 4, 1, 2], by: int.compare)
 ///    [1, 2, 3, 4, 4, 5, 6]
 ///
-pub fn sort(list: List(a), sort_by compare: fn(a, a) -> Order) -> List(a) {
+pub fn sort(list: List(a), by compare: fn(a, a) -> Order) -> List(a) {
   do_sort(list, compare, length(list))
 }
 

src/gleam/set.gleam

@@ -73,3 +73,17 @@ pub fn contains(in set: Set(element), this member: element) -> Bool {
 pub fn delete(from set: Set(element), this member: element) -> Set(element) {
   Set(map: map.delete(set.map, member))
 }
+
+/// Convert the set into a list of the contained elements.
+///
+/// The list has no specific ordering, any unintentional ordering may change in
+/// future versions of Gleam or Erlang.
+///
+/// ## Examples
+///
+///    > new() |> insert(2) |> to_list
+///    [2]
+///
+pub fn to_list(set: Set(element)) -> List(element) {
+  map.keys(set.map)
+}

test/gleam/set_test.gleam

@@ -1,5 +1,7 @@
 import gleam/should
 import gleam/set
+import gleam/list
+import gleam/int
 
 pub fn size_test() {
   set.new()
@@ -38,3 +40,13 @@ pub fn delete_test() {
   |> set.contains(1)
   |> should.be_false
 }
+
+pub fn to_list_test() {
+  set.new()
+  |> set.insert(2)
+  |> set.insert(3)
+  |> set.insert(4)
+  |> set.to_list
+  |> list.sort(by: int.compare)
+  |> should.equal([2, 3, 4])
+}