`functor (Config : ConfigInt.Type) (Text : UnicodeString.Type) -> sig type text = Text.t type index = Text.index val compare : ?locale:string -> ?prec:precision -> ?variable:variable_option -> text -> text -> int val sort_key : ?locale:string -> ?prec:precision -> ?variable:variable_option -> text -> string val compare_with_key : ?locale:string -> ?prec:precision -> ?variable:variable_option -> string -> text -> int val search_with_key : ?locale:string -> ?prec:precision -> ?variable:variable_option -> string -> text -> index -> index * index val search : ?locale:string -> ?prec:precision -> ?variable:variable_option -> text -> text -> index -> index * index end`