The acs package provides this S3 prompt method for
acs-class objects, primarily as a "helper" function to use in calls to
geography(object)<-, acs.units(object)<-, or
acs.colnames(object)<-. prompt provides an interactive
interface, prompting the user for new metadata values based on
the existing ones.
When what="geography" and geocols is not "all",
prompt will only prompt for replacements of the values of
geocols, but will still return values for all geography columns,
suitable for passing to geography(object)<-.
Anytime during the interactive prompt() session, a user may enter a
blank line to terminate, returning only the changed values
up to that point (along with the unchanged values for remaining entries.)