API Reference > bentleyjs-core > Utils > BeDuration BeDuration Class A duration of time. Can be either positive (towards future) or negative (in the past). BeDurations are immutable. Methods Name Description executeAfter<T>(fn: (...args: any[]) => T, scope?: any, ...args: any[]): Promise<T> Execute a function after delaying by this duration. minus(other: BeDuration): BeDuration Subtract a BeDuration from this BeDuration, returning a new BeDuration. plus(other: BeDuration): BeDuration Add a BeDuration to this BeDuration, returning a new BeDuration wait(): Promise<void> Utility function to just wait for the specified time fromMilliseconds(milliseconds: number): BeDuration Static Create a BeDuration from milliseconds. fromSeconds(seconds: number): BeDuration Static Create a BeDuration from seconds. race<T>(ms: number, promise: PromiseLike<T>): Promise<T | void> Static Utility function to wait for either the specified time or a promise, whichever resolves first wait(ms: number): Promise<void> Static Utility function to just wait for the specified time Properties Name Type Description isTowardsFuture Accessor ReadOnly boolean Determine whether this BeDuration is towards the future isTowardsPast Accessor ReadOnly boolean Determine whether this BeDuration is towards the past isZero Accessor ReadOnly boolean Determine whether this BeDuration is 0 seconds milliseconds Accessor ReadOnly number The duration in milliseconds seconds Accessor ReadOnly number Defined in core/bentley/src/Time.ts Line 13 Last Updated: 15 June, 2021