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let playEffect: ( WebAPI.GamepadAPI.gamepadHapticActuator, ~type_: WebAPI.GamepadAPI.gamepadHapticEffectType, ~params: WebAPI.GamepadAPI.gamepadEffectParameters=?,) => promise<WebAPI.GamepadAPI.gamepadHapticsResult>
let reset: WebAPI.GamepadAPI.gamepadHapticActuator => promise< WebAPI.GamepadAPI.gamepadHapticsResult,>