| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S Y S T E M . V A L _ U N S -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 1992-2006, 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, 51 Franklin Street, Fifth Floor, -- |
| -- Boston, MA 02110-1301, 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 contains routines for scanning modular Unsigned |
| -- values for use in Text_IO.Modular_IO, and the Value attribute. |
| |
| with System.Unsigned_Types; |
| |
| package System.Val_Uns is |
| pragma Pure; |
| |
| function Scan_Raw_Unsigned |
| (Str : String; |
| Ptr : access Integer; |
| Max : Integer) return System.Unsigned_Types.Unsigned; |
| -- This function scans the string starting at Str (Ptr.all) for a valid |
| -- integer according to the syntax described in (RM 3.5(43)). The substring |
| -- scanned extends no further than Str (Max). Note: this does not scan |
| -- leading or trailing blanks, nor leading sign. |
| -- |
| -- There are three cases for the return: |
| -- |
| -- If a valid integer is found, then Ptr.all is updated past the last |
| -- character of the integer. |
| -- |
| -- If no valid integer is found, then Ptr.all points either to an initial |
| -- non-digit character, or to Max + 1 if the field is all spaces and the |
| -- exception Constraint_Error is raised. |
| -- |
| -- If a syntactically valid integer is scanned, but the value is out of |
| -- range, or, in the based case, the base value is out of range or there |
| -- is an out of range digit, then Ptr.all points past the integer, and |
| -- Constraint_Error is raised. |
| -- |
| -- Note: these rules correspond to the requirements for leaving the pointer |
| -- positioned in Text_IO.Get |
| -- |
| -- Note: if Str is empty, i.e. if Max is less than Ptr, then this is a |
| -- special case of an all-blank string, and Ptr is unchanged, and hence |
| -- is greater than Max as required in this case. |
| |
| function Scan_Unsigned |
| (Str : String; |
| Ptr : access Integer; |
| Max : Integer) return System.Unsigned_Types.Unsigned; |
| -- Same as Scan_Raw_Unsigned, except scans optional leading |
| -- blanks, and an optional leading plus sign. |
| -- Note: if a minus sign is present, Constraint_Error will be raised. |
| -- Note: trailing blanks are not scanned. |
| |
| function Value_Unsigned |
| (Str : String) return System.Unsigned_Types.Unsigned; |
| -- Used in computing X'Value (Str) where X is a modular integer type whose |
| -- modulus does not exceed the range of System.Unsigned_Types.Unsigned. Str |
| -- is the string argument of the attribute. Constraint_Error is raised if |
| -- the string is malformed, or if the value is out of range. |
| |
| end System.Val_Uns; |
