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Implement a function that sets the milliseconds of a given date object to a specified value.

Write a function that takes a string and regular expression as inputs, and returns an array of all matches found using the String.matchAll() method.

Create a function that uses Array.prototype.findLast() to find the last element in an array that matches a given condition. Return the element if it exists or null if it does not.

Write a function that concatenates two strings using the String.prototype.concat() method.

Create a function that takes a string as input and returns the same string in uppercase letters using the `toString()` method of the String object.

Implement a function that removes all unused items in a Set collection

Create a function that will return an array in a localized way using the toLocaleString method.

Create a function that takes an array as input and returns a new array with the elements in reversed order.

Create a function that takes an array as input and returns an array of the keys of the given array using Array.prototype.keys() method.

Create a function that searches for the last index of a substring in an array using Array.prototype.lastIndexOf().

Create a function that normalizes a string using String.prototype.normalize method.

Create a function that takes in a string and a length and returns a new string with the original string padded with leading spaces if it is shorter than the provided length.

Write a function that returns an array of char codes from a string

Implement a function that adds a value to a set using Set.prototype.add().

A kata that requires the student to use String.prototype.split() to split a given string into substrings and perform a specified operation on them.

Write a function that takes a string and returns an array of matched patterns using String.prototype.matchAll().

Write a function that converts a given string to its string representation using the toString() method.

Create a function that takes a string and a number and pads that string with a specified character until it reaches the given length.

Write a function that takes a string and a search term and returns the index of the first occurrence of the search term in the given string. If the search term is not present in the string, return -1.

Implement a function that uses String.prototype.trimEnd() to trim whitespace at the end of a string.

Combine two arrays into a single array using the Array.prototype.concat() method

Write a function that can take in a list of numbers and precision cut them to a desired number of decimal places.

Implement equations using the Array.of() method to create arrays.

Write a function that checks if an element is present in an array using Array.prototype.includes() method.

Implement a function that uses String's padStart method to add leading zeros to a number string to ensure it always has a minimum length

Create a function that replaces all instances of a given substring with another string within a larger string using String.prototype.replaceAll() method.

Create a function that uses the String.prototype.lastIndexOf() method to find the index of the last occurrence of a specified substring in a given string.

Create a function that uses the copyWithin method to replace specified elements within an array.

This kata focuses on using String.prototype.indexOf() method.

Create a Stock Advisor that recommends which stocks to buy based on certain parameters.

Use Array.prototype.slice() to solve the following tasks.

Converts a given date to a time string

Write a function that normalizes a string using String.prototype.normalize().

Write a function that returns the nth number in the Fibonacci sequence using recursion.

Given a sentence, split it into an array of words using the String.prototype.split() method.

Implement a function that returns the character at the specified index of a given string.

Implement a function that takes a string as input and returns it in lower case.

Create a function that receives a string and a number n, the function should return the string repeated n times.

In this kata, you will be working with the String.prototype.toLocaleUpperCase() method to convert a string to uppercase according to the user's locale.

Implement the Array.prototype.with() method that returns a new array with the elements from the original array and the added elements.

Implement a function that takes in a Set and returns an array of entries

Create a function that takes two parameters: a string and a regular expression. The function should return an array of all matches found in the string using the regular expression.

Create a function that takes a start time and an event duration and returns the end time of the event, using the Date.prototype.setHours() method to set the hours of the start time.

Write a function that takes a date string as input and converts it to a UTC date string format.

Write a function that takes a string and a substring, and returns the index of the first occurrence of the substring in the string. If the substring is not found in the string, return -1.

Write a function that takes a Set object as a parameter and returns an array of keys using Set.prototype.keys().

Write a function that checks if a given string has a unicode character code point greater than or equal to 128. Use the String.prototype.codePointAt() method.

Implement a function that groups an array of objects by a given key and returns a new array of objects, where each object has a key and an array of objects that have that key.

Implement a function that returns true if a given string starts with a specific substring.

Create a function that concatenates two strings using the String.prototype.concat() method.

Write a function that takes a string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

Create a function that returns the current minutes.

Write a function that takes an array and a value and pushes the value to the end of the array using Array.prototype.push().

Create a function to search for a substring in a given string using String.prototype.search() method.

Create a function that takes a string and returns an array of the char codes for each character in the string

Write a function that returns the result of a string match with a given pattern.

Create a function that takes in a string and uses String.prototype.match() to find all occurrences of a pattern within the string.

Write a function that joins two arrays into a single string using Array.prototype.join() method.

Create a function that takes a year (YYYY) and returns the date object with its year set to the provided year.

Write a function that takes a date object and a number representing the desired month, and sets the month of the date to the given month.

Write a function that replaces the first occurrence of a specific string in a given string.

Implement the Array.prototype.unshift() method without using built-in functions

Write a function that uses the Date.prototype.getDay() method to determine the day of the week for a given date object.

Create a function that takes a Date object and returns a JSON string of the date in ISO format.

Write a JavaScript function to find the index of an item in an array using Array.prototype.findIndex().

Create a function that receives a string and normalizes it using the String.prototype.normalize() method. Apply the NFC normalization form.

Given an array of numbers and a start index, remove a certain number of elements from the array and replace them with new elements.

Implement a function that returns the current month from Date object using Date.prototype.getMonth()

Write a function that checks if every element in an array satisfies a given condition.

Write a function that takes in a date and returns the seconds within the minute in UTC time.

Create a function that returns the current year using Date's built-in getFullYear method

Create a function that takes two parameters: a string and a target substring, and returns the index of the first occurrence of the target substring in the string. If the target substring is not found, return -1.

Create a function that takes an array of numbers and returns the index of a given element. Use Array.prototype.findIndex() to implement the function.

Given two arrays, join them to create a new array.

Write a function that returns the value of a given string using the String.prototype.valueOf() method.

Create a function that transforms a given string to uppercase, using String.prototype.toLocaleUpperCase()

Create a function that repeats a given string n times.

Create a function that returns the month of a Date object in UTC time zone.

Create a function that takes two strings as input and concatenates them using the String.prototype.concat() method.

Write a function that uses recursion to calculate the factorial of a given positive integer.

Implement a function that takes a Date object and a number representing minutes and sets the UTC minutes of the Date object to the provided value. The function should return the updated Date object.

Create a function that takes an array and removes a portion of the array, as specified by the arguments, and returns the removed portion.

Write a function that takes a string and a substring as arguments, and finds the last occurrence of the substring in the string. If the substring is not found, return -1.

Write a function that takes in a string and a target substring, and returns the index at which the target substring is first found. If the target substring is not found in the string, return -1. Use the built-in JavaScript method `indexOf()` to solve the problem.

Create a function that takes in a string with extra white space at the beginning and end of the string, and returns a new string with that white space removed. Use String.prototype.trim().

Create a function that accepts a Set and a value to remove, and returns the updated Set after deleting the value.

Given a string, return a new string that is a substring of the original string. The substring should start at a specified index and continue until the end of the original string.

Create a function that checks if a given string ends with a specified suffix.

Create a function that replaces all occurrences of a substring with a new string.

Convert an array to a string with comma-separated values. The input array can contain numbers, strings, objects, or arrays.

Create a function that determines if two strings are anagrams of each other.

Write a function that returns the index of the first occurrence of a given element in an array using Array.prototype.indexOf(). If the element is not found in the array, return -1.

Sort an array of words based on their alphabetical order using String.prototype.localeCompare() method.

Implement normalize method to format a string removing all the accents

Write a function that checks if a given variable is an array. If it is an array, return true, otherwise return false.

Write a function that takes a string and a regular expression and returns an array of all the substrings in the string that match the regular expression.

Create a function that takes an array and a value as arguments and adds the value to the beginning of the array using the unshift() method.

Create a function that accepts a string and a target length. If the length of the string is less than the target length, pad the string with spaces at the beginning until the target length is reached. If the string length is greater than or equal to the target length, return the original string.

Write a function that takes a Date object and returns a string representing the time portion of the date in the current time zone using the toLocaleTimeString() method. The function should also take an optional argument specifying the locale to use.

Create a function that receives a Date object and returns the milliseconds that have elapsed since the start of the day.