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import type { λ } from "./types.ts";
const { performance } = globalThis;export const cancel = Symbol("throttle.cancel");
/** * Create a throttled function that invokes `fun` at most every `ms` milliseconds. * * `fun` is invoked with the last arguments passed to the throttled function. * * Calling `[throttle.cancel]()` on the throttled function will cancel the currently * scheduled invocation. */const throttle = Object.assign(  (fun: λ, ms: number, { leading = true, trailing = true } = {}) => {    let toId: any;    let lastInvoke = -Infinity;    let lastArgs: any[] | undefined;
    const invoke = () => {      lastInvoke = performance.now();      toId = undefined;      fun(...lastArgs!);    };
    return Object.assign(      (...args: any[]) => {        if (!leading && !trailing) return;        lastArgs = args;        const dt = performance.now() - lastInvoke;
        if (dt >= ms && toId === undefined && leading) invoke();        else if (toId === undefined && trailing) {          toId = setTimeout(invoke, dt >= ms ? ms : ms - dt);        }      },      { [cancel]: () => clearTimeout(toId) },    );  },  { cancel },) as  & (<T extends λ>(    fun: T,    ms: number,    opts?: { leading?: boolean; trailing: boolean },  ) => λ<Parameters<T>, void> & { [cancel](): void })  & {    cancel: typeof cancel;  };
export default throttle;