Lotide

A mini clone of the Lodash library.

Purpose

BEWARE: This library was published for learning purposes. It is not intended for use in production-grade software.

This project was created and published by me as part of my learnings at Lighthouse Labs.

Usage

Install it:

npm install @tjsmr/lotide

Require it:

const _ = require('@tjsmr/lotide');

Call it:

const results = _.tail([1, 2, 3]) // => [2, 3]

Documentation

The following javascript functions are currently implemented:

assertArraysEqual(arr1, arr2)

• Description: Compares two arrays and logs an assertion message indicating whether they are equal or not.

• Parameters:

  • arr1 (Array): The first array to compare.
  • arr2 (Array): The second array to compare.

• Returns: Passed if the arrays are equal, Failed otherwise using node assertArraysEqualTest.js; see description for use.

assertEqual(actual, expected)

• Description: Compares two values and logs an assertion message indicating whether they are equal or not.

• Parameters:

  • actual (Any): The actual value to compare.
  • expected (Any): The expected value to compare.

• Returns: Passed if the strings or integers are equal, Failed otherwise using node assertEqualTest.js; see description for use.

assertObjectsEqual(actual, expected)

• Description: Compares two objects and logs an assertion message indicating whether they are equal or not.

• Parameters:

  • actual (Object): The actual object to compare.
  • expected (Object): The expected object to compare.

• Returns: Passed if the objects are equal, Failed otherwise; see description for use.

findWaldo(names, found)

• Description: Searches for the name "Waldo" in an array and executes a callback function when found.

• Parameters:

  • names (Array): The array of names to search through.
  • found (Function): The callback function to execute when "Waldo" is found. It takes the index of "Waldo" as an argument.

• Returns: Found Waldo at index <index>!

countLetters(sentence)

• Description: Counts the occurrences of each letter in a sentence.

• Parameters:

  • sentence (String): The sentence to count the letters in.

• Returns: An object containing the counts of each letter.

countOnly(allItems, itemsToCount)

• Description: Counts the occurrences of specific items in an array based on provided criteria.

• Parameters:

  • allItems (Array): The array of items to be counted.
  • itemsToCount (Object): The object specifies the items to count and their criteria.

• Returns: An object containing the counts of the specified items.

eqArrays(arr1, arr2)

• Description: Checks if two arrays are equal.

• Parameters:

  • arr1 (Array): The first array to compare.
  • arr2 (Array): The second array to compare.

• Returns: true if the arrays are equal, false otherwise using node eqArraysTest.js.

eqObjects(object1, object2)

• Description: Checks if two objects are equal.

• Parameters:

  • object1 (Object): The first object to compare.
  • object2 (Object): The second object to compare.

• Returns: true if the objects are equal, false otherwise.

findKey(object, callback)

• Description: Finds a key in an object based on a provided callback function.

• Parameters:

  • object (Object): The object to search for a key in.
  • callback (Function): The callback function to execute for each key in the object. It takes the value of each key as an argument.

• Returns: The first key for which the callback function returns a truthy value, or undefined if no key is found.

findKeyByValue(object, value)

• Description: Finds a key in an object based on a provided value.

• Parameters:

  • object (Object): The object to search for a key in.
  • value (Any): The value to find a key for.

• Returns: The first key that corresponds to the provided value, or undefined if no key is found.

flatten(arr)

• Description: Flattens a nested array into a single-level array.

• Parameters:

  • arr (Array): The array to flatten.

• Returns: A new array with all nested elements flattened.

head(arr)

• Description: Retrieves the first element of an array.

• Parameters:

  • arr (Array): The array to retrieve the first element from.

• Returns: The first element of the array, or undefined if the array is empty.

letterPositions(sentence)

• Description: Maps the positions of each letter in a sentence.

• Parameters:

  • sentence (String): The sentence to map the letter positions for.

• Returns: An object containing arrays of positions for each letter.

map(arr, callback)

• Description: Creates a new array by applying a callback function to each element of the provided array.

• Parameters:

  • arr (Array): The array to map over.
  • callback (Function): The callback function to execute for each element of the array. It takes the element as an argument.

• Returns: A new array with the results of the callback function applied to each element.

middle(arr)

• Description: Retrieves the middle element(s) of an array.

• Parameters:

  • arr (Array): The array to retrieve the middle element(s) from.

• Returns: An array containing the middle element(s) of the array.

tail(arr)

• Description: Retrieves all elements of an array except for the first element.

• Parameters:

  • arr (Array): The array to retrieve the tail from.

• Returns: A new array containing all elements except for the first element of the array.

takeUntil(arr, callback)

• Description: Creates a new array by taking elements from the beginning of the provided array until the callback function returns a truthy value.

• Parameters:

  • arr (Array): The array to take elements from.
  • callback (Function): The callback function to execute for each element of the array. It takes the element as an argument.

• Returns: A new array with elements taken from the beginning of the original array until the callback function returns a truthy value.

without(source, itemsToRemove)

• Description: Creates a new array with elements from the source array excluding the specified items to remove.

• Parameters:

  • source (Array): The array to filter elements from.
  • itemsToRemove (Array): The array of items to remove from the source array.

• Returns: A new array containing elements from the source array excluding the specified items.

package.json:

• This file contains metadata about the project.

index:

• Alternatively, use require('./index') to import any function from the library.