Santa's Toy Factory — Utility Module

A grab-bag of reusable helpers: an event wrapper that smuggles extra data to listeners (SubscribeAgent), generic map/array extension methods (RemoveKey, RemoveAll), <localizes> message builders, number padding, a float ToString(Decimals), a hand-rolled ParseInt, and a keyframe-driven prop Shake. Teaches parametric types, extension functions, and localization.

From the Santa's Toy Factory Epic starter project (SampleVerse/SantaToyFactory/utility_module.verse). Epic Games reference Verse, shown for study.

• # This file defines the utility module that contains a number of extension functions, constants and functions for performing various tasks.
  
  using { /Fortnite.com/Devices }
  using { /Fortnite.com/Devices/CreativeAnimation }
  using { /UnrealEngine.com/Temporary/SpatialMath }
  using { /UnrealEngine.com/Temporary/UI }
  using { /Verse.org/Random }
  using { /Verse.org/Simulation }
  
  Utility<public> := module:
  
      # The factor to convert from LEGO® units (knobs) to Fortnite units (centimeters)
      LEGOUnitsToFortniteUnits<public> : float = 0.8 * 20.0
  
      # Extension functions for passing arguments with events.
      # Code taken from: https://dev.epicgames.com/community/snippets/d8k/fortnite-wrapping-subscribe-to-pass-additional-data-to-listeners.
      (Listenable : listenable(agent)).SubscribeAgent<public>(OutputFunc : tuple(agent, t)->void, ExtraData : t where t:type) : cancelable =
          Wrapper := wrapper_agent(t){ExtraData := ExtraData, OutputFunc := OutputFunc}
          Listenable.Subscribe(Wrapper.InputFunc)