Two points here. For a list L,
* "varnames(L)[i]" now works OK in git; and
* The alternative "varname(L[i])" now also works.
The first fix was just a matter of trivially generalizing something.
The second was kinda subtle: varname() required the ID number of a series,
while what you get from "L[i]" is an actual series, not its ID number. Now
varname() accepts either an ID number or a series itself.
Perfect! Many thanks!