Ok, read it. I'm having trouble understanding the ultimate goal (the request focuses on implementation rather than end goal).
The goal is global variables. Who wouldn't want that? We know have math(), regex() and many powerful things in MC. One remaining bit of the functionality puzzle is persistent variables so that we can apply data from one record across others in the database.
Do you have a specific example of something? I'm only asking so as to see if there is a way to accomplish your goal now.
I do
I track chart data in my library. I track each chart song and the weeks that it was in the charts and the position. The data might look like this:
Chart History: 1985\03\16>62;1985\03\23>48;1985\03\30>39;1985\04\06>35;1985\04\13>36;1985\04\20>37
Chart History, as you can see, is a ; delimited list of dates followed by > and the chart position for that week.
I also have a field called Chart Entry which is one date and tracks when a song enters the chart, eg
Chart Entry: 1985\03\23
What I want to do is create a smartlist that takes a single Chart Entry date from a random track and then pulls out the top 10 for that week from the Chart History data to create a playlist of the top ten tracks of any random week in chart history.
How I'd achieve this with variables is.
Playlist 1: Pull 1 random track. Copy the Chart Entry in Memory 1
Playlist 2: Pull all tracks where Memory 1 exists in the Chart History field and whose chart position at that date < 11
Random Top 10 Smartlist: Playlist 1 and Playlist 2 sort by chart position data
I cannot see how to achieve this without variables.
Regardless, who wouldn't want persistent variables if they were available? Every time we get a new piece of functionality it opens up multiple opportunities. This one I can see opening up many more. And it struck me how similar my variables are to the regex Rn values. The missing step is that the Rn values don't persist beyond the life of the expression they are contained within. If that could be modified, we could get global variables...