@likailiu/lotide v1.0.0

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 @likailiu/lotide

Require it:

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

Call it:

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

Documentation

The following functions are currently implemented:

• assertEqual(x, y): runs an assertion test on primitive values x and y to determine if x === y, printing pass/fail messages to the console.

• eqArrays(array1, array2): determines if the values in array1 and array2 are equal; only supports primitive values and nested arrays.

• eqObjects(object1, object2): determines if the key-value pairs in object1 and object2 are equal; supports primitive values, arrays and objects.

• assertArraysEqual(array1, array2): calls eqArrays on array1 and array2 and logs EQUAL/NOT EQUAL messages to the console.

• assertObjectsEqual(object1, object2): calls eqObjects on object1 and object2 and logs EQUAL/NOT EQUAL messages to the console.

• head(array): returns the "head" of an array: a new array containig the first element of the original array.

• middle(array): returns the "middle" of an array: a new array containing the middle element(s) of the original array.

• tail(array): returns the "tail" of an array: a new array containing the all the elements except for the first one of the original array.

• countLetters(string): returns an object of the numbers of each alphabetic letter (case insensitive) in a string.

• letterPositions(string): returns an object of each letter(case insensitive) in a string and all the indices they are at.

• isAlpha: returns true if an character is alphabetic and false if not; helps distinguish alphabetic characters from non-alphabetic characters in functions like countLetters and letterPositions, since they only work on alphabetic letters.

• countOnly(allItems, itemsToCount): returns an object of the item-number pairs based on how many times an item appears in the allItems array; only those items with a truthy value in itemsToCount will be counted.

• findKey(object, callback): returns the first property name in an object that, when passed to the callback function, leads to a return value of true.

• findKeyByValue(object, value): returns the first property name whose value is equal to the value passed in.

• map(array, callback): a home-made version of array.prototype.map(): returns an new array populated with the return values of the callback function when each element in the original array is passed as an argument.

• takeUntil(array, callback): returns a new array populated with the items in an array up until(not including) the first item that leads to a return value of true when passed as argument.

• without(sourceArray, itemsToRemove): returns a new array populated with the items that are in the source array but not in the itemsToRemove array, in the same order as the source array.