Just another update

Task/Set/00DESCRIPTION

@@ -11,8 +11,11 @@ Show each of these set operations:
 * A ⊆ B -- ''subset''; true if every element in set A is also in set B.
 * A = B -- ''equality''; true if every element of set A is in set B and vice-versa.
 
-As an option, show some other set operations. (If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.) As another option, show how to modify a mutable set.
+As an option, show some other set operations. (If A ⊆ B, but A ≠ B, then A is called a true or proper subset of B, written A ⊂ B or A ⊊ B.)
+As another option, show how to modify a mutable set.
 
-One might implement a set using an [[associative array]] (with set elements as array keys and some dummy value as the values). One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bitwise binary operators). The basic test, m ∈ S, is [[O]](n) with a sequential list of elements, O(''log'' n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
+One might implement a set using an [[associative array]] (with set elements as array keys and some dummy value as the values).
+One might also implement a set with a binary search tree, or with a hash table, or with an ordered array of binary bits (operated on with bitwise binary operators).
+The basic test, m ∈ S, is [[O]](n) with a sequential list of elements, O(''log'' n) with a balanced binary search tree, or (O(1) average-case, O(n) worst case) with a hash table.
 
 {{Template:See also lists}}

Task/Set/Prolog/set-2.pro

@@ -0,0 +1,55 @@
+%%  Set creation
+
+?- list_to_ord_set([1,2,3,4], A), list_to_ord_set([2,4,6,8], B).
+A = [1, 2, 3, 4],
+B = [2, 4, 6, 8].
+
+%% Test m ∈ S -- "m is an element in set S"
+
+?- ord_memberchk(2, $A).
+true.
+
+%% A ∪ B -- union; a set of all elements either in set A or in set B.
+
+?- ord_union($A, $B, Union).
+Union = [1, 2, 3, 4, 6, 8].
+
+%% A ∩ B -- intersection; a set of all elements in both set A and set B.
+
+?- ord_intersection($A, $B, Intersection).
+Intersection = [2, 4].
+
+%% A ∖ B -- difference; a set of all elements in set A, except those in set B.
+
+?- ord_subtract($A, $B, Diff).
+Diff = [1, 3].
+
+%% A ⊆ B -- subset; true if every element in set A is also in set B.
+
+?- ord_subset($A, $B).
+false.
+
+?- ord_subset([2,4], $B).
+true.
+
+%% A = B -- equality; true if every element of set A is in set B and vice-versa.
+
+?- $A == $B.
+false.
+
+?- $A == [1,2,3,4].
+true.
+
+%% Definition of a proper subset:
+
+ord_propsubset(A, B) :-
+    ord_subset(A, B),
+    \+(A == B).
+
+%% add/remove elements
+
+?- ord_add_element($A, 19, NewA).
+NewA = [1, 2, 3, 4, 19].
+
+?- ord_del_element($NewA, 3, NewerA).
+NewerA = [1, 2, 4, 19].

Task/Set/Python/set.py

@@ -1,49 +1,49 @@
 >>> s1, s2 = {1, 2, 3, 4}, {3, 4, 5, 6}
->>> s1 | s2; # Union
+>>> s1 | s2 # Union
 {1, 2, 3, 4, 5, 6}
->>> s1 & s2; # Intersection
+>>> s1 & s2 # Intersection
 {3, 4}
->>> s1 - s2; # Difference
+>>> s1 - s2 # Difference
 {1, 2}
->>> s1 < s1; # True subset
+>>> s1 < s1 # True subset
 False
->>> {3, 1} < s1; # True subset
+>>> {3, 1} < s1 # True subset
 True
->>> s1 <= s1; # Subset
+>>> s1 <= s1 # Subset
 True
->>> {3, 1} <= s1; # Subset
+>>> {3, 1} <= s1 # Subset
 True
->>> {3, 2, 4, 1} == s1; # Equality
+>>> {3, 2, 4, 1} == s1 # Equality
 True
->>> s1 == s2; # Equality
+>>> s1 == s2 # Equality
 False
->>> 2 in s1; # Membership
+>>> 2 in s1 # Membership
 True
->>> 10 not in s1; # Non-membership
+>>> 10 not in s1 # Non-membership
 True
->>> {1, 2, 3, 4, 5} > s1; # True superset
+>>> {1, 2, 3, 4, 5} > s1 # True superset
 True
->>> {1, 2, 3, 4} > s1; # True superset
+>>> {1, 2, 3, 4} > s1 # True superset
 False
->>> {1, 2, 3, 4} >= s1; # Superset
+>>> {1, 2, 3, 4} >= s1 # Superset
 True
->>> s1 ^ s2; # Symmetric difference
+>>> s1 ^ s2 # Symmetric difference
 {1, 2, 5, 6}
->>> len(s1); # Cardinality
+>>> len(s1) # Cardinality
 4
->>> s1.add(99); # Mutability
+>>> s1.add(99) # Mutability
 >>> s1
 {99, 1, 2, 3, 4}
->>> s1.discard(99); # Mutability
+>>> s1.discard(99) # Mutability
 >>> s1
 {1, 2, 3, 4}
->>> s1 |= s2; # Mutability
+>>> s1 |= s2 # Mutability
 >>> s1
 {1, 2, 3, 4, 5, 6}
->>> s1 -= s2; # Mutability
+>>> s1 -= s2 # Mutability
 >>> s1
 {1, 2}
->>> s1 ^= s2; # Mutability
+>>> s1 ^= s2 # Mutability
 >>> s1
 {1, 2, 3, 4, 5, 6}
 >>>

Task/Set/REXX/set.rexx

@@ -50,7 +50,7 @@ if add then do;  set_=_2;  t=_1;  s=_1;  end
     if (eq | subset) & \has  then return 0
     end    /*j*/
 
-if subset then return 1
-if eq then if arg()>3 then return 1
-                      else return set$('equal',_2,_1,1)
+if subset  then return 1
+if eq  then  if  arg()>3  then return 1
+                          else return set$('equal',_2,_1,1)
 return set.t