Data update

Task/Order-by-pair-comparisons/Gleam/order-by-pair-comparisons.gleam

@@ -0,0 +1,17 @@
+import gleam/io
+import gleam/list
+import gleam/order.{Gt, Lt}
+import in
+
+pub fn main() {
+  ["violet", "red", "green", "indigo", "blue", "yellow", "orange"]
+  |> list.sort(by: fn(a, b) {
+    io.print("Is " <> a <> " > " <> b <> "? (y/n) ")
+    case in.read_line() {
+      Ok("y\n") -> Gt
+      Ok(_) -> Lt
+      Error(_) -> panic as "Error reading from standard input."
+    }
+  })
+  |> echo
+}

Task/Order-by-pair-comparisons/Koka/order-by-pair-comparisons.koka

@@ -0,0 +1,41 @@
+import std/core/undiv
+import std/os/readline
+
+fun treesort(xs : list<string>, ?cmp: (string, string) -> e order) : e list<string>
+  recur/treesort(xs, Nil)
+
+fun recur/treesort(xs : list<string>, res : list<string>, ?cmp: (string, string) -> e order) : e list<string>
+  match(xs)
+    Cons(x, xx) ->
+      val (lo, hi) = partition(x, xx)
+      treesort(lo, Cons(x, treesort(hi, res.pretend-decreasing)).pretend-decreasing)
+    Nil -> res
+
+fun partition(^x : string, ys : list<string>, ?cmp: (string, string) -> e order)
+  match(ys)
+    Nil -> (Nil, Nil)
+    Cons(y, yy) ->
+      match ?cmp(y, x)
+        Lt ->
+          val (lo, hi) = partition(x, yy)
+          (Cons(y, lo), hi)
+        _ ->
+          val (lo, hi) = partition(x, yy)
+          (lo, Cons(y, hi))
+
+effect ask
+  fun ask(s1: string, s2: string): order
+
+fun main()
+  with handler
+    fun ask(s1, s2)
+      print("Is " ++ s1 ++ " <, =, or > " ++ s2 ++ "? ")
+      var done := Nothing
+      while {done.is-nothing}
+        match readline()
+          ">" -> done := Just(Gt)
+          "<" -> done := Just(Lt)
+          "=" -> done := Just(Eq)
+          _ -> println("Invalid input")
+      done.unjust
+  ["violet", "red", "green", "indigo", "blue", "yellow", "orange"].treesort(?cmp=ask)