Actions and functions use similar, but different syntax, because actions use a GUI. I like having the choice between command line and GUI, but it does make it more difficult to find examples that show the exact syntax of actions and/or functions and thus complicates the learning process. For example, $replace() can use multiple from/to arguments (and maybe can include multiple fields in it's string argument?) but that doesn't tell me, or us, if and how the replace action can use multiple arguments.
One way to work around this would be to focus on learning the functions syntax. This would work if there is a way to create an action that is effectively a script of functions...and operators, commands, etc., for that matter. So, is there a way to create an action that is made up of script functions, using the exact function syntax?
I'm now suspecting that Replace with regular expression is the closest one can come to what I'm looking for. If so, a very brief answer will be understood. I hope I haven't wasted anyone's time.
I am not sure I understand your request correctly.
You could have a look here to see how «Action Groups» are working. If you combine several single and simple actions together into one collection - called Action Group - you can apply as many changes as you need with one single click.
It is often easier to have 10 different actions for 10 different tags to keep full control over the result. if you write one very complex action it is more difficult to find an error or define some exceptions. In addition you run the risk to don't recognize the use case anymore in a month or a year.
Feel free to ask for a specific use case where you need assistance.