# File lib/mongo/collection.rb, line 527 def create_index(spec, opts={}) opts[:dropDups] = opts[:drop_dups] if opts[:drop_dups] field_spec = parse_index_spec(spec) opts = opts.dup name = opts.delete(:name) || generate_index_name(field_spec) name = name.to_s if name generate_indexes(field_spec, name, opts) name end