| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S Y S T E M . V A L _ E N U M -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 1992-2000, 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 2, 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. See the GNU General Public License -- |
| -- for more details. You should have received a copy of the GNU General -- |
| -- Public License distributed with GNAT; see file COPYING. If not, write -- |
| -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- |
| -- MA 02111-1307, USA. -- |
| -- -- |
| -- As a special exception, if other files instantiate generics from this -- |
| -- unit, or you link this unit with other files to produce an executable, -- |
| -- this unit does not by itself cause the resulting executable to be -- |
| -- covered by the GNU General Public License. This exception does not -- |
| -- however invalidate any other reasons why the executable file might be -- |
| -- covered by the GNU Public License. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- This package is used to compute the Value attribute for enumeration types |
| -- other than those in packages Standard and System. See unit Exp_Imgv for |
| -- details of the format of constructed image tables. |
| |
| package System.Val_Enum is |
| pragma Pure (Val_Enum); |
| |
| function Value_Enumeration_8 |
| (Names : String; |
| Indexes : System.Address; |
| Num : Natural; |
| Str : String) |
| return Natural; |
| -- Used to compute Enum'Value (Str) where Enum is some enumeration type |
| -- 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 parameter Num is the value N - 1 (i.e. Enum'Pos (Enum'Last)). |
| -- The reason that Indexes is passed by address is that the actual type |
| -- is created on the fly by the expander. |
| -- |
| -- Str is the argument of the attribute function, and may have leading |
| -- and trailing spaces, and letters can be upper or lower case or mixed. |
| -- If the image is found in Names, then the corresponding Pos value is |
| -- returned. If not, Constraint_Error is raised. |
| |
| function Value_Enumeration_16 |
| (Names : String; |
| Indexes : System.Address; |
| Num : Natural; |
| Str : String) |
| return Natural; |
| -- Identical to Value_Enumeration_8 except that it handles types |
| -- using array (0 .. Num) of Natural_16 for the Indexes table. |
| |
| function Value_Enumeration_32 |
| (Names : String; |
| Indexes : System.Address; |
| Num : Natural; |
| Str : String) |
| return Natural; |
| -- Identical to Value_Enumeration_8 except that it handles types |
| -- using array (0 .. Num) of Natural_32 for the Indexes table. |
| |
| end System.Val_Enum; |