The comma separated data is entered by a user and I want to keep it as simple as possible, so extra quoting is something I want to avoid.

I felt that escaped commas and backslashes was just about OK, or two commas and two backslashes also just about OK, but the more complex it gets the harder it is for the user. I am happy to add extra load to the script to help the user.

I have included some code to handle simple input errors such as a space inserted in a command: '-- text' instead of '--text'.