@pmcall/lotide v1.0.2

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 @pmcall/lotide

Require it:

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

Call it:

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

Documentation

The following functions are currently implemented:

• assertArraysEqual(array, array): An assertion which compares two arrays and returns a statement confirming if it is true or false.

  [1, 2, 3] & [1, 2, 3] //returns true
  [1, 2, 3] & [3, 2, 1] //returns false

• assertEqual(value, value): An assertion which compares two primative values and returns a statement confirming if it is true or false.

  	```js

  1 & 2 //returns false "banana" & "banana" //returns true

• assertObjectsEqual(object, object):An assertion which compares two objects to see if they deeply match and returns a statement confirming if it is true or false.

  { colour: "Yellow" } & { colour: "Yellow" } //returns true 
  { name: "John" } & { name: "Jane" } //returns false

• countLetters(string): Returns an object which contains a count for each letter found in the string; excludes spaces.

  	```js

  "banana" //returns { b: 1, a: 3, n: 2}

• countOnly(array, object): Takes an array of strings and an object which specifies which strings are to be counted marked by true. Returns an object which contains the counts for each of the items to be counted.

  array = ["banana", "pineapple", "mango", "mango", "papaya"]
  object = {"banana": true, "mango": true, "papaya": false}
  //returns {"banana": 1, "mango": 2}

• eqArrays(string): Compares two arrays and returns true if their contents match.

  	```js

  1, 2, 3 & 1, 2, 3 //returns true 1, 2, 3 & 3, 2, 1 //returns false

• eqObjects(object, object): Compares two objects and returns true if their contents match.

  	```js

  { a: "hello", b: "goodbye" } & { b: "goodbye", a: "hello" } //returns true { a: "banana", b: "mango" } & { b: "manana", a: "bango" } //returns false

• findKeyByValue(object, value): Searches an object and returns the first key which contains a value matching the given criteria.

  	```js

  critera = "orange" { banana: "Yellow", pineapple: "Yellow", tangerine: "orange", yuzu: "Yellow" } //returns "tangerine"

• findKey(object, callback): Similar to findKeyByValue as it searches an object and returns the first key which contains a value matching the given criteria. However, this uses a callback method instead of a simple value.

  callback = x => x.count === 4
  { "dogs": { "count" = 2 }, "cats": { "count": 3 },  "capybaras": { "count": 4 } } //returns capybaras

• flatten(nested array): Returns a flattened array from a nested array.

  [1, 2, [3, 4], 5] //returns [1, 2, 3, 4, 5]

• head(array): Returns the head (the item at the first index) of an array.

  [1, 2, 3] //returns [1]

• letterPositions(string): Returns an object which contains a key for each letter found in the string and an array of the indices of the poisiton of the letters.

  	```js

  "Hello" //returns { H: 0 , E: 1 , L: 2, 3 , O: 4 }

• map(array, callback): A version of map which returns a newly created array based on the callback function specified.

  callback = x => x[0]
  ["banana", "peach", "apple", "mango", "lychee"] //returns ["b", "p", "a", "m", "l"]

• middle(array): Returns the item(s) at the mid-point of an array. If the array has one item at the exact midpoint, one item is returned; if the mid-point is between two items, both items are returned.

  	```js
  	[1, 2, 3] //returns [2]

  1, 2, 3, 4 //returns 2, 3

  	```

• tail(array): Returns the tail (all items following the first index) of an array.

  	```js

  1, 2, 3 //returns 2, 3

• takeUntil(array, callback): Takes an array until the conditions of the callback are met, then returns the array.

  	```js

  callback = x => x < 0 1, 2, -1, 3 //returns 1, 2

• without(array, array): Takes an array and returns an array with any specified items removed.

  	```js

  "This", "is", "not", "a", "pen" & "not" //returns "This", "is", "a", "pen"