1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- S Y S T E M . V A L _ I N T --
9 -- Copyright (C) 1992-2006, Free Software Foundation, Inc. --
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 2, 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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNAT was originally developed by the GNAT team at New York University. --
30 -- Extensive contributions were provided by Ada Core Technologies Inc. --
32 ------------------------------------------------------------------------------
34 with System.Unsigned_Types; use System.Unsigned_Types;
35 with System.Val_Uns; use System.Val_Uns;
36 with System.Val_Util; use System.Val_Util;
38 package body System.Val_Int is
47 Max : Integer) return Integer
52 Minus : Boolean := False;
53 -- Set to True if minus sign is present, otherwise to False
56 -- Saves location of first non-blank (not used in this case)
59 Scan_Sign (Str, Ptr, Max, Minus, Start);
61 if Str (Ptr.all) not in '0' .. '9' then
63 raise Constraint_Error;
66 Uval := Scan_Raw_Unsigned (Str, Ptr, Max);
68 -- Deal with overflow cases, and also with maximum negative number
70 if Uval > Unsigned (Integer'Last) then
71 if Minus and then Uval = Unsigned (-(Integer'First)) then
74 raise Constraint_Error;
80 return -(Integer (Uval));
85 return Integer (Uval);
93 function Value_Integer (Str : String) return Integer is
95 P : aliased Integer := Str'First;
97 V := Scan_Integer (Str, P'Access, Str'Last);
98 Scan_Trailing_Blanks (Str, P);