RosettaCodeData/Task/Topological-sort/Ada/topological-sort-3.ada

43 lines
1.5 KiB
Ada

private with Ada.Containers.Indefinite_Vectors;
generic
type Index_Type_With_Null is new Natural;
package Set_Of_Names is
subtype Index_Type is Index_Type_With_Null
range 1 .. Index_Type_With_Null'Last;
-- manage a set of strings;
-- each string in the set is assigned a unique index of type Index_Type
type Set is tagged private;
-- inserts Name into Names; do nothing if already there;
procedure Add(Names: in out Set; Name: String);
-- Same operation, additionally emiting Index=Names.Idx(Name)
procedure Add(Names: in out Set; Name: String; Index: out Index_Type);
-- remove Name from Names; do nothing if not found
-- the removal may change the index of other strings in Names
procedure Sub(Names: in out Set; Name: String);
-- returns the unique index of Name in Set; or 0 if Name is not there
function Idx(Names: Set; Name: String) return Index_Type_With_Null;
-- returns the unique name of Index;
function Name(Names: Set; Index: Index_Type) return String;
-- first index, last index and total number of names in set
-- to iterate over Names, use "for I in Names.Start .. Names.Stop loop ...
function Start(Names: Set) return Index_Type;
function Stop(Names: Set) return Index_Type_With_Null;
function Size(Names: Set) return Index_Type_With_Null;
private
package Vecs is new Ada.Containers.Indefinite_Vectors
(Index_Type => Index_Type, Element_Type => String);
type Set is new Vecs.Vector with null record;
end Set_Of_Names;