CycleImplement a function that takes one or more values and returns a function that cycles through those values each time it is called
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Type Utilities IIImplement utilities to determine non-primitive variable types in JavaScript
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Count ByImplement a function that counts the number of times a value appears in an array based on a function or property name
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CurryImplement a function that transforms a function that takes multiple arguments into a function that can be repeatedly called with only one argument at a time
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DebounceImplement a function to limit how many times a function can be executed by delaying the execution of the function until after a specified time after its last execution attempt
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PromisifyImplement a function that takes a function following the common error-first callback style and returns a version that returns promises
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ThrottleImplement a function to control the execution of a function by limiting how many times it can execute over time
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ClassnamesImplement a function that conditionally joins CSS class names together
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Data MergingImplement a function to merge rows of data from the same user
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Event EmitterImplement a class that can subscribe to and emit events that trigger attached callback functions
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FlattenImplement a function that recursively flattens an array into a single level deep
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getElementsByStyleImplement a function to get all DOM elements that are rendered using the specified style
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HTML SerializerImplement a function to serialize an object into an HTML string with indentation
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JSON.stringifyImplement a function that converts a JavaScript value into a JSON string
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List FormatImplement a function that formats a list of items into a single readable string
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MemoizeImplement a function that returns a memoized version of a function which accepts a single argument
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Promise.allImplement the Promise.all() function that resolves to an array of results if all the input elements are resolved or rejects otherwise
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Promise.anyImplement the Promise.any() function that resolves when any of the input elements are resolved
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Squash ObjectImplement a function that returns a new object after squashing the input object into a single level of depth
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Deep CloneImplement a function that performs a deep copy of a value
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Deep EqualImplement a function that determines if two values are equal
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getElementsByClassNameImplement a function to get all DOM elements that contain the specified classes
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Map Async LimitImplement a function that maps an array of items with an asynchronous mapping function while not exceeding the concurrency limit
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Deep OmitImplement a function that removes specified keys and their corresponding values from an object, including nested objects or arrays
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ClampPremiumImplement a function to clamp a number within the inclusive lower and upper bounds
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Function LengthPremiumImplement a function that returns the number of parameters expected by a function
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Number of ArgumentsPremiumImplement a function that returns the number of arguments it was called with
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SleepPremiumImplement a function that pauses for a specified duration before resuming execution
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Array.prototype.squarePremiumImplement a custom Array.prototype.square() method that squares the values in an array
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Cancellable IntervalPremiumImplement a function that acts like setInterval but returns a function to cancel the interval
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Cancellable TimeoutPremiumImplement a function that acts like setTimeout but returns a function to cancel the pending callback
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ChunkPremiumImplement a function that creates an array of elements split into smaller groups of a specified size
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CompactPremiumImplement a function that creates an array with all falsey values removed
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DifferencePremiumImplement a function that finds the difference in values between arrays
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Drop Right WhilePremiumImplement a function that excludes elements from the end of an array until the predicate returns false
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Drop WhilePremiumImplement a function that excludes elements from the beginning of an array until the predicate returns false
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FillPremiumImplement a function that fills an array with values within specified indices
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Find IndexPremiumImplement a function that returns the index of the first element in the array that satisfies the provided testing function
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Find Last IndexPremiumImplement a function that returns the index of the last element in the array that satisfies the provided testing function
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From PairsPremiumImplement a function that returns an object composed from key-value pairs
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Function.prototype.applyPremiumImplement the Function.prototype.apply() function that calls the function with a given `this` value and arguments as an array
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GetPremiumImplement a function to safely access deeply-nested properties in JavaScript objects
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In RangePremiumImplement a function to check if a number falls between two numbers
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IntersectionPremiumImplement a function that computes the intersection of arrays, returning a new array containing unique values present in all given arrays
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Max ByPremiumImplement a function that finds the maximum element based on the specified criteria
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Object MapPremiumImplement a function to transform values within an object
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OncePremiumImplement a function that accepts a callback and restricts its invocation to at most once
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Promise.rejectPremiumImplement a function to return a Promise object rejected with a reason
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RangePremiumImplement a function that returns a sequence of numbers in ascending order
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Range RightPremiumImplement a function that returns a sequence of numbers in descending order
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SingletonPremiumImplement a Singleton class that ensures a class has only one instance while providing a global point of access to that instance
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Unique ArrayPremiumImplement a function to remove all duplicate values from an array
ComposePremiumImplement a function that takes multiple functions as arguments and returns a new function that applies those functions in reverse
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Function.prototype.bindPremiumImplement the Function.prototype.bind() function that creates a new function with the `this` keyword set to a provided value
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jQuery.cssPremiumImplement a jQuery-like function that sets the style of a DOM element
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Promise.racePremiumImplement the Promise.race() function that resolves or rejects when any of the input elements are resolved or rejected
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SizePremiumImplement a function that returns the size of collection
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SumPremiumImplement a function that sums numbers by accepting a number and allows for repeated calling with more numbers until it is not called with any number
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Make Counter IIPremiumImplement a function that returns a counter object with methods to retrieve and manipulate the value
Group ByPremiumImplement a function that groups values in an array based on a function or property name
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Intersection ByPremiumImplement a function that returns an array of unique values that are included in all given arrays based on a provided iteratee function
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Intersection WithPremiumComputes the intersection of arrays using a custom comparator function to determine equality between elements
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Is EmptyPremiumImplement a function to check if a value is an empty object, collection, map, or set
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LimitPremiumImplement a function that accepts a callback and restricts its invocation to at most N times
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Promise MergePremiumImplement a function to merge the results of two promises into a single value
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Promise TimeoutPremiumImplement a function that resolves a promise if it is fulfilled within a timeout period and rejects otherwise
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Promise.resolvePremiumImplement a function to resolve a given value to a Promise
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Promise.withResolversPremiumImplement a function that returns an object containing a new `Promise` object and two functions to resolve or reject it
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Promisify IIPremiumImplement a promisify function that allows the original function to override the return value
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TurtlePremiumImplement a Turtle class that moves a turtle on a 2D plane
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Union ByPremiumImplement a function that creates an array of unique values, in order, from all given arrays.
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Camel Case KeysPremiumImplement a function to convert all the keys in an object to camel case
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Compact IIPremiumImplement a function that returns an object with all falsey values removed
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Conforms ToPremiumImplement a function that checks if object conforms to source
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Curry IIPremiumImplement a function that transforms a function that takes multiple arguments into a function that can be repeatedly called with any number of arguments
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Debounce IIPremiumImplement a debounce function that comes with a cancel method to cancel delayed invocations and a flush method to immediately invoke them
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Event Emitter IIPremiumImplement a class that can subscribe to and emit events that trigger attached callback functions. Subscription objects are returned and can unsubscribe itself
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getElementsByTagNamePremiumImplement a function to get all DOM elements that match a tag
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Identical DOM TreesPremiumImplement a function to determine if two DOM trees are the same
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jQuery Class ManipulationPremiumImplement a set of jQuery-like functions that manipulates classes on a DOM element
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Map AsyncPremiumImplement a function that maps an array of items with an asynchronous mapping function
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Promise.allSettledPremiumImplement the Promise.allSettled() function that resolves to an array of outcomes when all the input elements are either resolved or rejected
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Resumable IntervalPremiumImplement a function that creates a resumable interval object
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Text SearchPremiumImplement a function to highlight text if a searched term appears within it
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Deep MapPremiumImplement a function to recursively transform values
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Text Search IIPremiumImplement a function to highlight text if searched terms appear within it
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Deep MergePremiumImplement a function that merges two objects together
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Memoize IIPremiumImplement a function that returns a memoized version of a function which accepts any number of arguments
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Curry IIIPremiumImplement a function which transforms a function which takes variadic arguments into a function that can be repeatedly called with any number of arguments
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Classnames IIPremiumImplement a function that conditionally joins CSS class names together and also handles de-duplication and function values
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Backbone ModelPremiumImplement a class resembling Backbone.Model which allows storing of attributes/values and responding to changes in specific attribute values
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Data SelectionPremiumImplement a function to filter rows of data matching a specified requirement