tasks a-s

Task/Set/Icon/set-1.icon

@@ -0,0 +1,61 @@
+procedure display_set (s)
+  writes ("[")
+  every writes (!s || " ")
+  write ("]")
+end
+
+# fail unless s1 and s2 contain the same elements
+procedure set_equals (s1, s2)
+  return subset(s1, s2) & subset(s2, s1)
+end
+
+# fail if every element in s2 is not contained in s1
+procedure subset (s1, s2)
+  every (a := !s2) do {
+    if not(member(s1,a)) then fail
+  }
+  return s2
+end
+
+procedure main ()
+  a := set(1, 1, 2, 3, 4)
+  b := set(2, 3, 5)
+  writes ("a: ")
+  display_set (a)
+  writes ("b: ")
+  display_set (b)
+  # basic set operations
+  writes ("Intersection: ")
+  display_set (a ** b)
+  writes ("Union: ")
+  display_set (a ++ b)
+  writes ("Difference: ")
+  display_set (a -- b)
+  # membership
+  if member(a, 2) then
+    write ("2 is a member of a")
+  else
+    write ("2 is not a member of a")
+  if member(a, 5) then
+    write ("5 is a member of a")
+  else
+    write ("5 is not a member of a")
+  # equality
+  if set_equals(a, set(1,2,3,4,4)) then
+    write ("a equals set(1,2,3,4,4)")
+  else
+    write ("a does not equal set(1,2,3,4,4)")
+  if set_equals(a, b) then
+    write ("a equals b")
+  else
+    write ("a does not equal b")
+  # subset
+  if subset(a, set(1,2)) then
+    write ("(1,2) is included in a")
+  else
+    write ("(1,2) is not included in a")
+  if subset(a, set(1,2,5)) then
+    write ("(1,2,5) is included in a")
+  else
+    write ("(1,2,5) is not included in a")
+end

Task/Set/Icon/set-2.icon

@@ -0,0 +1,39 @@
+link sets
+
+procedure main ()
+  a := set(1, 1, 2, 3, 4)
+  b := set(2, 3, 5)
+  write ("a: ", simage(a))
+  write ("b: ", simage(b))
+  # basic set operations
+  write ("Intersection: ", simage (a**b))
+  write ("Union: ", simage        (a++b))
+  write ("Difference: ", simage   (a--b))
+  # membership
+  if member(a, 2) then
+    write ("2 is a member of a")
+  else
+    write ("2 is not a member of a")
+  if member(a, 5) then
+    write ("5 is a member of a")
+  else
+    write ("5 is not a member of a")
+  # equality
+  if seteq(a, set(1,2,3,4,4)) then
+    write ("a equals set(1,2,3,4,4)")
+  else
+    write ("a does not equal set(1,2,3,4,4)")
+  if seteq(a, b) then
+    write ("a equals b")
+  else
+    write ("a does not equal b")
+  # check subset
+  if setlt(set(1,2), a) then
+    write ("(1,2) is included in a")
+  else
+    write ("(1,2) is not included in a")
+  if setlt(a, set(1,2,5), a) then
+    write ("(1,2,5) is included in a")
+  else
+    write ("(1,2,5) is not included in a")
+end