Roku Developer Program

Join our online forum to talk to Roku developers and fellow channel creators. Ask questions, share tips with the community, and find helpful resources.
cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
roIt
Reel Rookie

Linked List implementation

Hi there,

I'd like to implement a Linked List of objects (https://en.wikipedia.org/wiki/Linked_list) in BritghtScript. The problem I am facing is that it seems there's no References to objects in BrightScript. I am not sure if I am missing something or if that's actually a case.

Any help would be appreciated.

0 Kudos
3 REPLIES 3
rokenbuzz
Binge Watcher

Re: Linked List implementation

Associative arrays can be used like objects. Maybe that's what you're missing.

0 Kudos
JFalcon
Reel Rookie

Re: Linked List implementation

Actually, there is a way you can do this.  If we assume a one-directional linked list, we can create a function that returns our object which stores some data for the node.  I'll start with a function that creates a node object and provides a method for setting the next object:

function CreateNode(d)
	node = {
		SetNext	: function (x) : m.Next = x : return x : end function
		GetNext : function () : return m.Next : end function
		NextNode: Invalid
		Data: d
	}
	return node
end function

My SetNext() function will take a node object and set its next object, returning the object for further manipulation.  I'll use GetNext() in order to walk the linked list later.  (You could simplify this a bit I'm sure since I'm very new to BrightScript).

In my Main() function for testing purposes, I'll create a root node object, then add a few nodes to it.  I'll use a string for my node data, but you could use any other type of object you create (note the types are roAssociativeArray values for the nodes themselves).

	' Create root node
	root = CreateNode("Hello World! ")
	
	' Add nodes to each one returned
	nextNode = root.SetNext(CreateNode("Hello Next Node! "))
	nextNode = nextNode.SetNext(CreateNode("Another Node! "))
	nextNode = nextNode.SetNext(CreateNode("Last Node!"))
	
	' Start from root
	node = root
	result = ""
	
	' Walk nodes until no more found
	while node <> Invalid
        result = result + node.Data
		node = node.GetNext()
	end while
	
	' Print the combined string
	print result

If you run upload this app, compile and run it, you should see the following in the developer console:

Hello World! Hello Next Node! Another Node! Last Node!

Cheers!

Never criticize another unless you have walked a mile in their shoes. That way, if they get angry, you are a mile away and you have their shoes.
roIt
Reel Rookie

Re: Linked List implementation

This looks like a great suggestion! Will try it out, thanks!

0 Kudos
Need Assistance?
Welcome to the Roku Community! Feel free to search our Community for answers or post your question to get help.

Become a Roku Streaming Expert!

Share your expertise, help fellow streamers, and unlock exclusive rewards as part of the Roku Community. Learn more.