The `ellipsis?' procedure in psyntax.ss does exactly this, but it isn't available to user code. Re-implementing it is not possible without accessing internal details like the special identifier #{ $sc-ellipsis }# and without resorting to hacks.

Thus, I would like to ask to add `ellipsis?' to the list of procedures exported by Guile (like `identifier?` or `bound-identifier=?` already are).

-- Marc