--
-- Copyright (C) 1996 Ada Resource Association (ARA), Columbus, Ohio.
-- Author: David A. Wheeler
--

package body Ustrings is

  Input_Line_Buffer_Length : constant := 1024;
    -- If an input line is longer, Get_Line will recurse to read in the line.


  procedure Swap(Left, Right : in out Unbounded_String) is
    -- Implement Swap.  This is the portable but slow approach.
    Temporary : Unbounded_String;
  begin
    Temporary := Left;
    Left := Right;
    Right := Temporary;
  end Swap;

  function Empty(S : Unbounded_String) return Boolean is
   -- returns True if Length(S)=0.
  begin
   return (Length(S) = 0);
  end Empty;
 

  -- Implement Unbounded_String I/O by calling Text_IO String routines.


  -- Get_Line gets a line of text, limited only by the maximum number of
  -- characters in an Unbounded_String.  It reads characters into a buffer
  -- and if that isn't enough, recurses to read the rest.

  procedure Get_Line (File : in File_Type; Item : out Unbounded_String) is

    function More_Input return Unbounded_String is
       Input : String (1 .. Input_Line_Buffer_Length);
       Last  : Natural;
    begin
       Get_Line (File, Input, Last);
       if Last < Input'Last then
          return   To_Unbounded_String (Input(1..Last));
       else
          return   To_Unbounded_String (Input(1..Last)) & More_Input;
       end if;
    end More_Input;

  begin
      Item := More_Input;
  end Get_Line;


  procedure Get_Line(Item : out Unbounded_String) is
  begin
    Get_Line(Current_Input, Item);
  end Get_Line;

  procedure Put(File : in File_Type; Item : in Unbounded_String) is
  begin
    Put(File, To_String(Item));
  end Put;

  procedure Put(Item : in Unbounded_String) is
  begin
    Put(Current_Output, To_String(Item));
  end Put;

  procedure Put_Line(File : in File_Type; Item : in Unbounded_String) is
  begin
    Put(File, Item);
    New_Line(File);
  end Put_Line;

  procedure Put_Line(Item : in Unbounded_String) is
  begin
    Put(Current_Output, Item);
    New_Line;
  end Put_Line;

end Ustrings;

--
-- Permission to use, copy, modify, and distribute this software and its
-- documentation for any purpose and without fee is hereby granted,
-- provided that the above copyright and authorship notice appear in all
-- copies and that both that copyright notice and this permission notice
-- appear in supporting documentation.
-- 
-- The ARA makes no representations about the suitability of this software
-- for any purpose.  It is provided "as is" without express
-- or implied warranty.
-- 

You may also see the corresponding specification.

You may also see the list of program units.

You may return to the Program Small Home Page.

This hypertext format was generated by David A. Wheeler's ada2html