I'm trying to customize vim folding style and stuck with indentation. I know it has been asked multiple times here and I use this command (which seem to work for others) to test the appearance of fold:
:set foldtext=' '.foldtext()
This however gives me 'unknown option' error. Apparently, it doesn't accept the string containing only space(s), because this
:set foldtext='mytext'.foldtext()
works fine and adds 'mytext' to the beginning of folds.
Why doesn't it work and what's the way around it?