1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- S Y S T E M . V A L _ E N U M -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 1992-2009, Free Software Foundation, Inc. -- 10-- -- 11-- GNAT is free software; you can redistribute it and/or modify it under -- 12-- terms of the GNU General Public License as published by the Free Soft- -- 13-- ware Foundation; either version 3, or (at your option) any later ver- -- 14-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 15-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 16-- or FITNESS FOR A PARTICULAR PURPOSE. -- 17-- -- 18-- As a special exception under Section 7 of GPL version 3, you are granted -- 19-- additional permissions described in the GCC Runtime Library Exception, -- 20-- version 3.1, as published by the Free Software Foundation. -- 21-- -- 22-- You should have received a copy of the GNU General Public License and -- 23-- a copy of the GCC Runtime Library Exception along with this program; -- 24-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 25-- <http://www.gnu.org/licenses/>. -- 26-- -- 27-- GNAT was originally developed by the GNAT team at New York University. -- 28-- Extensive contributions were provided by Ada Core Technologies Inc. -- 29-- -- 30------------------------------------------------------------------------------ 31 32-- This package is used to compute the Value attribute for enumeration types 33-- other than those in packages Standard and System. See unit Exp_Imgv for 34-- details of the format of constructed image tables. 35 36package System.Val_Enum is 37 pragma Pure; 38 39 function Value_Enumeration_8 40 (Names : String; 41 Indexes : System.Address; 42 Num : Natural; 43 Str : String) 44 return Natural; 45 -- Used to compute Enum'Value (Str) where Enum is some enumeration type 46 -- other than those defined in package Standard. Names is a string with 47 -- a lower bound of 1 containing the characters of all the enumeration 48 -- literals concatenated together in sequence. Indexes is the address 49 -- of an array of type array (0 .. N) of Natural_8, where N is the 50 -- number of enumeration literals in the type. The Indexes values are 51 -- the starting subscript of each enumeration literal, indexed by Pos 52 -- values, with an extra entry at the end containing Names'Length + 1. 53 -- The parameter Num is the value N - 1 (i.e. Enum'Pos (Enum'Last)). 54 -- The reason that Indexes is passed by address is that the actual type 55 -- is created on the fly by the expander. 56 -- 57 -- Str is the argument of the attribute function, and may have leading 58 -- and trailing spaces, and letters can be upper or lower case or mixed. 59 -- If the image is found in Names, then the corresponding Pos value is 60 -- returned. If not, Constraint_Error is raised. 61 62 function Value_Enumeration_16 63 (Names : String; 64 Indexes : System.Address; 65 Num : Natural; 66 Str : String) 67 return Natural; 68 -- Identical to Value_Enumeration_8 except that it handles types 69 -- using array (0 .. Num) of Natural_16 for the Indexes table. 70 71 function Value_Enumeration_32 72 (Names : String; 73 Indexes : System.Address; 74 Num : Natural; 75 Str : String) 76 return Natural; 77 -- Identical to Value_Enumeration_8 except that it handles types 78 -- using array (0 .. Num) of Natural_32 for the Indexes table. 79 80end System.Val_Enum; 81