Use let

In the case of "value", as result of Swift 1.2:

  "let constants have been generalized to no longer require immediate
   initialization. The new rule is that a let constant must be initialized
   before use (like a var), and that it may only be initialized: not reassigned
   or mutated after initialization." - via release notes

dshb/BatteryWidget.swift

@@ -72,7 +72,7 @@ struct BatteryWidget: Widget {
 
 
     mutating func draw() {
-        var charge = battery.charge()
+        let charge = battery.charge()
         meters[0].draw(String(Int(battery.charge())),
                        percentage: charge / 100.0)
 

dshb/TMPWidget.swift

@@ -80,7 +80,7 @@ struct TMPWidget: Widget {
 
     mutating func draw() {
         for var i = 0; i < meters.count; ++i {
-            var value = 0.0
+            let value: Double
             switch meters[i].name {
                 case "BATTERY":
                     value = battery.temperature()