jungle_beats: A Ruby repository from lingtran

layout	title
page	Jungle Beat

Project Overview

Silly sounds that can be played by being backed by a linked list.

Linked Lists

Linked Lists are one of the most fundamental Computer Science data structures. A Linked List models a collection of data as a series of "nodes" which link to one another in a chain.

In a singly-linked list (the type we will be building) you have a head, which is a node representing the "start" of the list, and subsequent nodes which make up the remainder of the list.

The list itself can hold a reference to one thing -- the head node.

Each node can hold a single element of data and a link to the next node in the list.

The last node of the list is often called its tail.

Using sweet ASCII art, it might look like this:

List -- (head) --> ["hello" | -]-- (link) --> ["world" | -]-- (link) --> ["!" | ]

The three nodes here hold the data "hello", "world", and "!". The first two nodes have links which point to other nodes. The last node, holding the data "!", has no reference in the link spot. This signifies that it is the end of the list.

Learning Goals / Areas of Focus

Practice breaking a program into logical components
Distinguishing between classes and instances of those classes
Understanding how linked lists work to store and find data
Testing components in isolation and in combination

Functionality

Exercise the functionality from a Pry session:

require "./lib/jungle_beat"
> jb = JungleBeat.new("deep dep dep deep")
> jb.play
=> 4 # also plays the sounds
> jb.append("deep bop bop deep")
=> 4
> jb.all
=> "deep dep dep deep deep bop bop deep"
> jb.prepend("tee tee tee tee")
=> 4 # number of beats inserted
> jb.all
=> "tee tee tee tee deep dep dep deep deep bop bop deep"
> jb.include?("dep")
=> true
> jb.pop(4)
=> "deep bop bop deep"
> jb.all
=> "tee tee tee tee deep dep dep deep"
> jb.count
=> 8
> jb.insert(4, "boop bop bop boop")
=> "tee tee tee tee boop bop bop boop deep dep dep deep"
> jb.find(8, 2)
=> "deep dep"

Internal Structure

A Linked List stores the beats. Each node contains only a single "word"/beat. EAch of the following features for the list can be implemented:

append an element to the end of the list
prepend an element at the beginning of the list
insert one or more elements at an arbitrary position in the list
includes? gives back true or false whether the supplied value is in the list
pop one or more elements from the end of the list
count the number of elements in the list
find one or more elements based on arbitrary positions in the list. The first parameter indicates the first position to return and the second parameter specifies how many elements to return.
all return all elements in the linked list in order

Resources