     vsrc = Variable(name: "src", value: i)
     vdst = Variable(name: "dst", value: i)
     dests.append(vdst!)
-    StayConstraint(variable: vsrc!, strength: NORMAL)
-    ScaleConstraint(src: vsrc!, scale: scale, offset: offset, dest: vdst!,
-        strength: REQUIRED)
+    let _ = StayConstraint(variable: vsrc!, strength: NORMAL)
+    let _ = ScaleConstraint(src: vsrc!, scale: scale, offset: offset,
+        dest: vdst!, strength: REQUIRED)
   }
 
   let src = vsrc!

  let first = vfirst!
  let last = vlast!

  StayConstraint(variable: last, strength: STRONG_DEFAULT)
  let edit = EditConstraint(variable: first, strength: PREFERRED)
  let plan = planner.extractPlanFromConstraints([edit])
  for i in 0..<100 {

  for i in 0...n {
    let v = Variable(name: "v", value: 0)
    if let p = prev {
      let _ = EqualityConstraint(v1: p, v2: v, strength: REQUIRED)
    }
    if i == 0 {
      vfirst = v
