before

function

Creates a function that invokes func, with the this binding and arguments of the created function, while it's called less than n times.

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Installation

Import

import { before } from '@tulx/utils';

Source Code

Implementation

/**
 * Creates a function that invokes func, with the this binding and arguments of the created function, while it's called less than n times.
 *
 * @param n - The number of calls at which func is no longer invoked.
 * @param func - The function to restrict.
 * @returns Returns the new restricted function.
 *
 * @example
 * ```ts
 * jQuery(element).on('click', before(5, addContactToList));
 * // Allows adding up to 4 contacts to the list.
 * ```
 */
// eslint-disable-next-line @typescript-eslint/no-explicit-any
export function before<T extends (...args: any[]) => any>(
  n: number,
  func: T
): (...args: Parameters<T>) => ReturnType<T> | undefined {
  if (n < 1) {
    return () => undefined;
  }

  let count = 0;
  let result: ReturnType<T>;

  return function (
    this: unknown,
    ...args: Parameters<T>
  ): ReturnType<T> | undefined {
    if (count < n) {
      count++;
      result = func.apply(this, args) as ReturnType<T>;
      return result;
    }
    return result;
  };
}

Example

import { before } from '@tulx/utils';

jQuery(element).on('click', before(5, addContactToList));
// Allows adding up to 4 contacts to the list.

Related Functions

after

The opposite of before; this method creates a function that invokes func once it's called n or more times.

ary

Creates a function that invokes func, with up to n arguments, ignoring any additional arguments.

bind

Creates a function that invokes func with the this binding of thisArg and partials prepended to the arguments it receives.

bindKey

Creates a function that invokes the method at object[key] with partials prepended to the arguments it receives.

curry

Creates a function that accepts arguments of func and either invokes func returning its result, or returns a function that accepts the remaining arguments.

curryRight

This method is like curry except that arguments are applied to func in the manner of partialRight instead of partial.