[chaley]

General program mode templates do not go between {} characters. They must begin with the word 'program:' and the program goes until the end of the string. The concept of a multiline template goes away, because the entire string is one template. It makes little sense to me for someone to use a general program mode template in the situation you are describing. If they *really* need something of that complexity to generate a field value, then they can use a composite column or build a python template function.

Template program mode expressions can in theory be multiline, but in practice they never are. I think it is safe not to support them.

One thing that my suggestion does not cover is fields that contain explicit newlines, where these newlines are significant. Non-multiple text fields come to mind. These normally use HTML, so I am not convinced this is a problem. Is it?

BTW: I have no particular problem with adding a parameter to safe_formatter not to collapse white space. I just want to be sure it is needed before I do it. If I do this, then you could pass the entire string in one go. The downside is that there would be no white space processing, so templates like
"abc {series} def" would evaluate to "abc def" (two spaces) if there is no series. Perhaps this is OK.