------------------------------------------------------------------------------
--                                                                          --
--                         GNAT RUNTIME COMPONENTS                          --
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--            A D A . S T R I N G S . U N B O U N D E D . A U X             --
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--          Copyright (C) 1992-1998, Free Software Foundation, Inc.         --
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------------------------------------------------------------------------------

--  This child package of Ada.Strings.Unbounded provides some specialized
--  access functions which are intended to allow more efficient use of the
--  facilities of Ada.Strings.Unbounded, particularly by other layered
--  utilities (such as GNAT.Patterns).

package Ada.Strings.Unbounded.Aux is
pragma Preelaborate (Aux);

   function Get_String (U  : Unbounded_String) return String_Access;
   pragma Inline (Get_String);
   --  This function returns the internal string pointer used in the
   --  representation of an unbounded string. There is no copy involved,
   --  so the value obtained references the same string as the original
   --  unbounded string. The characters of this string may not be modified
   --  via the returned pointer, and are valid only as long as the original
   --  unbounded string is not modified. Violating either of these two
   --  rules results in erroneous execution.
   --
   --  This function is much more efficient than the use of To_String
   --  since it avoids the need to copy the string. The lower bound of the
   --  referenced string returned by this call is always one.

   procedure Set_String (UP : in out Unbounded_String; S : String);
   pragma Inline (Set_String);
   --  This function sets the string contents of the referenced unbounded
   --  string to the given string value. It is significantly more efficient
   --  than the use of To_Unbounded_String with an assignment, since it
   --  avoids the necessity of messing with finalization chains. The lower
   --  bound of the string S is not required to be one.

   procedure Set_String (UP : in out Unbounded_String; S : String_Access);
   pragma Inline (Set_String);
   --  This version of Set_String takes a string access value, rather than a
   --  string. The lower bound of the string value is required to be one, and
   --  this requirement is not checked.

end Ada.Strings.Unbounded.Aux;
