top_function_of top_function_of : hol_error -> string
Extract last function name added to a hol_error.
An invocation top_function_of holerr returns the
function name of the top origin element held in
holerr.
> top_function_of
(mk_hol_error "Foo" "bar" locn.Loc_Unknown "bad input")
val it = "bar": string
The call fails if the origin stack of the
hol_error is empty.
Feedback, Feedback.mk_hol_error,
Feedback.origins_of,
Feedback.message_of,
Feedback.top_structure_of,
Feedback.top_location_of,
Feedback.set_top_function