I can’t find anything about it online, and there don’t seem to be any methods using it in julia, so I decided to ask here.
Something like text/julia (or maybe text/x-julia for standard compliance?) is what I would expect.
It would be useful to be able to use repr(x, "text/julia") to get a julia expression that evaluates to x. you can often get this with just show(x), but that doesn’t work for everything (eg. Base.TTY).