Passing 2 Text Strings to Applescript Action

Question

I am trying to make a Automator Workflow that Checks if an RSS Feed has Changed & if there is a change then Tweet the New Update.
I have managed to get the URL and Extract the Text from the feed. and limit it to just the very latest 1 Item from the feed, Then i  have 2 Variables set-up one Called OldText and Another Called NewText.
I Need to compare the 2 Variables for any change.
In an applescript action i tried the following
on run {input, OldText, NewText}
          if NewText = OldText then beep
          return input
end run
I Get a Syntax Error
current application, current application} doesn’t match the parameters {input, OldText, NewText } for run.
I was using beep just for testing code will work
can it not pass 2 variables at a time ?

Answer 1

The parameters to an Automator action are already defined - you can't just put in your own.  In the case of the Run AppleScript action, the run handler is defined as:
   on run {input, parameters}
where the input parameter is a list (even if there is only one item) of the items passed from the previous action, and the parameters parameter is a list of the user interface settings (text fields, check boxes, etc) and options of the action itself.  If you are passing items to your script from previous actions in your workflow, you can get the desired item number from the input list (e.g. item 2 of input - I am guessing that you would know the order), and to get the value of a named variable from the workflow you can just ask Automator, for example:
   set oldText to (get value of variable "oldText" of front workflow)