blob: 3cdb532dc37ea08f0e3d3795d21596d577e13a67 [file] [log] [blame]
------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- S Y S T E M . W I D _ E N U M --
-- --
-- S p e c --
-- --
-- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This package contains the routine used for Enumeration_Type'Width
package System.Wid_Enum is
pragma Pure;
function Width_Enumeration_8
(Names : String;
Indexes : System.Address;
Lo, Hi : Natural)
return Natural;
-- Used to compute Enum'Width where Enum is some enumeration subtype
-- other than those defined in package Standard. Names is a string with
-- a lower bound of 1 containing the characters of all the enumeration
-- literals concatenated together in sequence. Indexes is the address
-- of an array of type array (0 .. N) of Natural_8, where N is the
-- number of enumeration literals in the type. The Indexes values are
-- the starting subscript of each enumeration literal, indexed by Pos
-- values, with an extra entry at the end containing Names'Length + 1.
-- The reason that Indexes is passed by address is that the actual type
-- is created on the fly by the expander.
--
-- Lo and Hi are the Pos values of the lower and upper bounds of the
-- subtype. The result is the value of Width, i.e. the maximum value
-- of the length of any enumeration literal in the given range.
function Width_Enumeration_16
(Names : String;
Indexes : System.Address;
Lo, Hi : Natural)
return Natural;
-- Identical to Width_Enumeration_8 except that it handles types
-- using array (0 .. Num) of Natural_16 for the Indexes table.
function Width_Enumeration_32
(Names : String;
Indexes : System.Address;
Lo, Hi : Natural)
return Natural;
-- Identical to Width_Enumeration_8 except that it handles types
-- using array (0 .. Num) of Natural_32 for the Indexes table.
end System.Wid_Enum;