     class func resetRelatedConstraintFrom(view:UIView, isHorizontal horizontal:Bool) {
         assert(!NSThread.isMainThread(), _fy_noMainQueueAssert)
         singleton.storedConstraints.forEach { constraint in
-            if let _from = constraint.from {
-                if _from == view {
-                    if horizontal == constraint.direction.horizontal {
-                        switch constraint.direction {
-                        case .RightLeft:
-                            constraint.to.fy_left(view.chainRight + constraint.value)
-                        case .LeftRigt:
-                            constraint.to.fy_right(view.chainLeft + constraint.value)
-                        case .BottomTop:
-                            constraint.to.fy_top(view.chainBottom + constraint.value)
-                        case .TopBottom:
-                            constraint.to.fy_bottom(view.chainTop + constraint.value)
-                        }
+            if let _from = constraint.from where _from == view {
+                if horizontal == constraint.direction.horizontal {
+                    switch constraint.direction {
+                    case .RightLeft:
+                        constraint.to.fy_left(view.chainRight + constraint.value)
+                    case .LeftRigt:
+                        constraint.to.fy_right(view.chainLeft + constraint.value)
+                    case .BottomTop:
+                        constraint.to.fy_top(view.chainBottom + constraint.value)
+                    case .TopBottom:
+                        constraint.to.fy_bottom(view.chainTop + constraint.value)
                     }
                 }
-            } else {
-                singleton.storedConstraints.remove(constraint)
             }
         }
     }

        var _constraints = constraints
        _constraints.forEach { constraint in
            if constraint.from == view {
                let _from = constraint.from
                let _to = constraint.to
                let _value = constraint.value

                    _to.rulerX.c = _from.superview!.frame.width - _from.frame.origin.x + _value
                }
                _constraints.remove(constraint)
            }
        }
        return _constraints
