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let clearWatch: (WebAPI.GeolocationAPI.geolocation, int) => unit
let getCurrentPosition: ( WebAPI.GeolocationAPI.geolocation, ~successCallback: WebAPI.GeolocationAPI.positionCallback, ~errorCallback: WebAPI.GeolocationAPI.positionErrorCallback=?, ~options: WebAPI.GeolocationAPI.positionOptions=?,) => unit
let watchPosition: ( WebAPI.GeolocationAPI.geolocation, ~successCallback: WebAPI.GeolocationAPI.positionCallback, ~errorCallback: WebAPI.GeolocationAPI.positionErrorCallback=?, ~options: WebAPI.GeolocationAPI.positionOptions=?,) => int