Library

Write a function that takes a date and returns the year in the hh:mm:ss format.

Implement a function that takes an array of strings and a search string, and returns a new array containing only the strings that includes the search string using String.prototype.includes() method.

Create a function that greets the user depending on the current hour of the day.

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

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

Create a function that takes a string and a number as arguments, and pads the string on the right side with spaces until the string reaches the desired length.

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

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

Implement a function that checks if all elements from an array are included in a given Set using the built-in Set.prototype.has() method.

Implement normalize method to format a string removing all the accents

Write a function that takes two arrays as arguments and concatenates them into a new array using the Array.prototype.concat() 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

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

Implement a function that removes leading and trailing whitespace from a string using the String.prototype.trim() method.

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 date object and a number representing the desired month, and sets the month of the date to the given month.

Create a function that takes in two parameters, a string and a substring, and checks if the string includes the substring. Return a boolean value.

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.

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.

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

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

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

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 takes in a string and checks if it starts with a given substring. Return a boolean indicating whether or not the string starts with the given substring.

Write a function that takes a string and returns an array of code points for each character in the string using String.prototype.codePointAt() method.

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

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

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

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

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

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

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

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

Create a function that slices a string based on a given start and end indexes

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

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

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.

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

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

Implement a function that replaces all instances of a specified substring in a given string.

Implement a function that concatenates a given string 'n' times using the String.prototype.repeat() method.

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

Create a function that takes a string and a number, and repeats the string the given number of times.

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

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

Create a function that returns an array of values of an array using the Array.prototype.values() method.

Create a function that concatenates two strings using the String.prototype.concat() method. The function should take two string parameters and return the concatenated string.

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 an Inventory Management System that allows users to add, remove and update items in the inventory.

Write a function that takes a string as input and splits it into an array of words using String.prototype.split(). Then, join the array back into a string using Array.prototype.join(). Finally, return the new string with a different delimiter separating each word.

Given an array of person objects, sort them alphabetically by their last name using String.prototype.localeCompare().

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 concatenates two strings using the String.prototype.concat() method.

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

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

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

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

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

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

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

Create a function that receives a string and a number as parameters. The function should return the string repeated `n` times, where n is the number passed as parameter.

Create a function that uses Array.prototype.entries() to iterate over an array and perform some operations.

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.

Write a function that returns whether a given string ends with the provided suffix or not

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

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

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

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 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.

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.

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.

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

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

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

Write a function that takes an array of numbers and returns their sum, using Array.prototype.reduceRight().

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

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

Converts a given date to a time string

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

Create a function that receives a string and a regular expression pattern and returns an array of all the occurrences of the pattern in the string using String.prototype.matchAll().

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

Write a function that takes an integer n and returns the nth Fibonacci number using recursion.

Write a function that takes a date object and a number of seconds and returns a new date object with the seconds set to the provided value. Example input: setSeconds(new Date('2022-10-10T10:10:10'), 30) Expected output: new Date('2022-10-10T10:10:30')

Fill arrays with specific values using Array.prototype.fill()

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

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

Create a function that takes a string as input and returns the string in all lowercase letters.

Write a function that takes a string and returns all its substrings of length 3 or greater. You must use String.prototype.slice() to achieve this.

Create a function that uses Array.prototype.every() to check if all the elements in an array meet a certain condition.

Write a function that takes in a string and uses precision cutting to remove all occurrences of the letter 'e'. Return the resulting string.

Create a function that takes an array and reverse its order in place.

Write a function that takes an array and a value as arguments and returns the index of the last occurrence of that value in the array using Array.prototype.lastIndexOf(). If the value is not found, return -1.

Write a function that finds the last index of a given element in an array using the Array.prototype.findLastIndex method.

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 sorts an array of strings in alphabetical order using String.prototype.localeCompare()

Write a function that takes a Date object and returns the date formatted in the user's local format using the toLocaleDateString() method.

Create a function that returns the current minutes.