Declartive Linked List

Declarative Linked List is a Node.js library that provides a straightforward and intuitive way to work with linked lists using higher-order functions. It allows you to manipulate linked lists in a declarative manner, making your code more concise and expressive.

Installation

You can install Declarative Linked List via npm:

npm install declarative-linked-list

Get Started:

const DoublyLinkedList = require('declarative-linked-list');

Create a new linked list.

const list = new DoublyLinkedList();

For manual operations.

list.head
list.tail
list.size
node.next
node.prev
node.data

Get size.

list.Size()
list.IsEmpty()

Prepend elements to the list.

list.Prepend(1);
list.PrependMany(2, 3, 4);

Append elements to the list

list.Append(3);
list.AppendMany(4, 5, 6);

Get a value by index.

const value = list.Get(3);

Print out the list in a readable format.

const display = list.PrintForward()
const display = list.PrintBackward()

Insert element at a specific index.

list.InsertAt(2, 10);

Delete the first element.

list.DeleteFirst();

Delete the last element.

list.DeleteLast();

Delete element at a specific index.

list.DeleteAt(2);

Copy the hole linked list or a portion of it by adding start and end index.

const copy = list.Copy();
const copyPortion = list.Copy(1, 3);

Reverse the linked list. Returns a copy of the linked list.

const reversed = list.Reverse();

Concatenate two linked lists

const list2 = new DoublyLinkedList();
list2.Append(5);
list.Concat(list2);

Convert the linked list to array or string.

const arr = list.ToArray();
const str = list.ToString();

Apply a function to each element in the list in place.

list.ForEach(x => x * 2);

Map each element in the list to a new value.

const mappedList = list.Map(x => x * 2);

Filter elements based on a condition.

const filteredList = list.Filter(x => x < 5);

Find the first occurrence of an element that satisfies a condition.

const found = list.Find(x => x === 3);

Find the last occurrence of an element that satisfies a condition.

const lastFound = list.FindLast(x => x === 3);

Find the index of the first occurrence of an element that satisfies a condition.

const index = list.FindIndex(x => x === 3);

Find the index of the last occurrence of an element that satisfies a condition.

const lastIndex = list.FindLastIndex(x => x === 3);

Reduce the elements of the list to a single value

const sum = list.Reduce((acc, curr) => acc + curr, 0);

Sort the elements of the list. It Determines the order by the values 1, 0 and -1. 1 as greater, -1 as smaller and 0 as equal.

• Numbers

const sortedList = list.Sort((a, b) => a - b); 

• Strings

const sortedList = list.Sort((a, b) => a.localeCompare(b));

• Have fun with it, Here is an example of ordering according to card symbols.

const goalOrder = ['A', 'K', 'Q', 'J']
const sortedList = list.Sort((a, b) => goalOrder.indexOf(a) < goalOrder.indexOf(b) ? -1 : 1);

API Methods:

• PrintForward(): Print out in a string format from the head.

• PrintBackward(): Print out in a string format from the tail.

• Size(): Get the size.

• IsEmpty(): True or false.

• Get(index): Returns a value by index.

• Prepend(value): Inserts an element at the beginning of the list.

• Append(value): Inserts an element at the end of the list.

• PrependMany(...values): Inserts multiple elements at the beginning of the list.

• AppendMany(...values): Inserts multiple elements at the end of the list.

• InsertAt(index, value): Inserts an element at a specific index in the list.

• DeleteFirst(): Deletes the first element of the list.

• DeleteLast(): Deletes the last element of the list.

• DeleteAt(index): Deletes the element at a specific index in the list.

• Copy(): Copy the hole linked list.

• Copy(startIndex, endIndex): Copies a portion of the list specified by the start and end indices.

• Reverse(): Reverses the order of elements in the list.

• Concat(otherList): Concatenates the current list with another list.

• ForEach(callback): Applies a function to each element in the list.

• Map(callback): Maps each element in the list to a new value using a function.

• Filter(predicate): Filters elements based on a condition.

• Find(predicate): Finds the first element that satisfies a condition.

• FindLast(predicate): Finds the last element that satisfies a condition.

• FindIndex(predicate): Finds the index of the first element that satisfies a condition.

• FindLastIndex(predicate): Finds the index of the last element that satisfies a condition.

• Reduce(callback, initialValue): Reduces the elements of the list to a single value.

• Sort(compareFunction): Sorts the elements of the list using a compare function.

Contributing:

Contributions are welcome! If you have any suggestions, bug reports, or feature requests, please open an issue or submit a pull request on GitHub.

License

This project is licensed under the standard ISC License.

Feel free to customize the README further based on your preferences and additional information you'd like to include!