--- a/src/Pure/General/set.ML Sun Apr 23 20:15:53 2023 +0200
+++ b/src/Pure/General/set.ML Sun Apr 23 21:31:00 2023 +0200
@@ -24,6 +24,7 @@
val member: T -> elem -> bool
val subset: T * T -> bool
val eq_set: T * T -> bool
+ val ord: T ord
val insert: elem -> T -> T
val make: elem list -> T
val merge: T * T -> T
@@ -278,9 +279,24 @@
fun subset (set1, set2) = forall (member set2) set1;
+
+(* equality and order *)
+
fun eq_set (set1, set2) =
pointer_eq (set1, set2) orelse size set1 = size set2 andalso subset (set1, set2);
+val ord =
+ pointer_eq_ord (fn (set1, set2) =>
+ (case int_ord (size set1, size set2) of
+ EQUAL =>
+ (case get_first (fn a => if member set2 a then NONE else SOME a) set1 of
+ NONE => EQUAL
+ | SOME a =>
+ (case get_first (fn b => if member set1 b then NONE else SOME b) set2 of
+ NONE => EQUAL
+ | SOME b => Key.ord (a, b)))
+ | order => order));
+
(* insert *)
--- a/src/Pure/library.ML Sun Apr 23 20:15:53 2023 +0200
+++ b/src/Pure/library.ML Sun Apr 23 21:31:00 2023 +0200
@@ -210,6 +210,8 @@
val dict_ord: ('a * 'b -> order) -> 'a list * 'b list -> order
val length_ord: 'a list * 'b list -> order
val list_ord: ('a * 'b -> order) -> 'a list * 'b list -> order
+ val vector_ord: 'a ord -> 'a vector ord
+ val array_ord: 'a ord -> 'a array ord
val sort: 'a ord -> 'a list -> 'a list
val sort_distinct: 'a ord -> 'a list -> 'a list
val sort_strings: string list -> string list
@@ -957,6 +959,12 @@
fun length_ord (xs, ys) = int_ord (length xs, length ys);
fun list_ord elem_ord = length_ord ||| dict_ord elem_ord;
+fun vector_ord ord =
+ pointer_eq_ord (int_ord o apply2 Vector.length ||| Vector.collate ord);
+
+fun array_ord ord =
+ pointer_eq_ord (int_ord o apply2 Array.length ||| Array.collate ord);
+
(* sorting *)