Adding custom commands to messages

[Fiona]

Hiya, I've got a little script that injects some behaviour into the PokeBattle_Trainer class.

All good, but I wanted to add some behaviour to the messaging system. I dug into the Kernel.pbMessageDisplay method and found all the regex that does the command replacement. I added my additional behaviour and it's all cool. But I don't like that I had to edit the Essentials code. (I can't share it easily!)

Is there a mechanism I'm missing to add my own commands to the messaging system so my script can be kept siloed?

I suppose I could alias pbMessageDisplay, do the substitution and pass it back along to the original. But I think that would only work for my script and I couldn't do the same thing for any additional scripts. If I'm wrong about this please tell me, I only started using Ruby yesterday.

Thanks for any help.

 

[Luka S.J.]

It all really depends on what behaviour you want to add to Kernel.pbMessageDisplay. If it's something simple, like passing through a scene update, the function accepts blocks that you can give it

Kernel.pbDisplayMessage(*args){ var = "string" }

For more complex stuff, you will have to alias it or completely overwrite the function, if you want to make it standalone.

 

[Fiona]

I want to add additional substitutions to the message text. I don't think passing it a block would help.

Yeah I said I suppose I could alias it and add the functionality as a sort of text pre-processor, but I'm not sure how to achieve that in such a way that it wouldn't be overriden by doing the same trick in a different script. I think maybe I don't fully understand function aliases in Ruby.

[edit]

Okay I just tried experimenting with alias_method and I'm getting errors about Kernel not being a class. So I guess I now have a new question: How do I successfully alias a method on the Kernel class without directly overriding it in it's entirety?

 

[Luka S.J.]

It goes a little something like this:

# reference to the Kernel module
module Kernel
  # references self as class
  class << self
    # doesn't alias if already aliased
   unless Kernel.respond_to?(:pbMessageDisplay_Old)
      # aliases to the new name
      alias pbMessageDisplay_Old pbMessageDisplay
      # creates new functionality
      def pbMessageDisplay(*args)
        args[1] = "I like shorts! They're comfy and easy to wear!"
        # reference back to the original function
        return pbMessageDisplay_Old(*args)
      end # def end
    end # unless end
  end # class end
end # module end

This code is a bit bloated though to avoid double aliasing and "Stack level too deep" errors (which mainly pop up when soft-resetting).

 

[Fiona]

Thanks a lot for that, that "class << self" singleton thing is a fun little bit of Ruby magic. It's a shame it can't be re-aliased but meh, it'll be good enough for now. :)

I reallly appreciate your help!

 

[Marin]

It's a shame it can't be re-aliased

If with this you mean not being able to alias this same method again -- you can. Just make sure to call the second alias something different. You'll end up with a Stack level too deep otherwise.

 

[Fiona]

Ah I see, that's a good tip, thank you Marin :)

@Luke S.J. I've posted the script that this was needed for as a resource, I hope you're okay with the credit I threw on https://reliccastle.com/resources/157/