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1996-09-28
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------------------------------------------------------------------------------
-- --
-- GNAT RUNTIME COMPONENTS --
-- --
-- A D A . S T R I N G S . W I D E _ S E A R C H --
-- --
-- B o d y --
-- --
-- $Revision: 1.6 $ --
-- --
-- Copyright (c) 1992,1993,1994 NYU, All Rights Reserved --
-- --
-- The GNAT library is free software; you can redistribute it and/or modify --
-- it under terms of the GNU Library General Public License as published by --
-- the Free Software Foundation; either version 2, or (at your option) any --
-- later version. The GNAT library is distributed in the hope that it will --
-- be useful, but WITHOUT ANY WARRANTY; without even the implied warranty --
-- of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU --
-- Library General Public License for more details. You should have --
-- received a copy of the GNU Library General Public License along with --
-- the GNAT library; see the file COPYING.LIB. If not, write to the Free --
-- Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. --
-- --
------------------------------------------------------------------------------
with Ada.Strings.Wide_Maps; use Ada.Strings.Wide_Maps;
package body Ada.Strings.Wide_Search is
-----------------------
-- Local Subprograms --
-----------------------
function Belongs
(Element : Wide_Character;
Set : Wide_Maps.Wide_Character_Set;
Test : Membership)
return Boolean;
pragma Inline (Belongs);
-- Determines if the given element is in (Test = Inside) or not in
-- (Test = Outside) the given character set.
-------------
-- Belongs --
-------------
function Belongs
(Element : Wide_Character;
Set : Wide_Maps.Wide_Character_Set;
Test : Membership)
return Boolean is
begin
if Test = Inside then
return Is_In (Element, Set);
else
return not Is_In (Element, Set);
end if;
end Belongs;
-----------
-- Count --
-----------
function Count
(Source : in Wide_String;
Pattern : in Wide_String;
Mapping : in Wide_Maps.Wide_Character_Mapping := Wide_Maps.Identity)
return Natural
is
N : Natural;
J : Natural;
begin
if Pattern = "" then
raise Pattern_Error;
end if;
-- Handle the case of non-identity mappings by creating a mapped
-- string and making a recursive call using the identity mapping
-- on this mapped string.
if Mapping /= Wide_Maps.Identity then
declare
Mapped_Source : Wide_String (Source'Range);
begin
for J in Source'Range loop
Mapped_Source (J) := Value (Mapping, Source (J));
end loop;
return Count (Mapped_Source, Pattern);
end;
end if;
N := 0;
J := Source'First;
while J <= Source'Last - (Pattern'Length - 1) loop
if Source (J .. J + (Pattern'Length - 1)) = Pattern then
N := N + 1;
J := J + Pattern'Length;
else
J := J + 1;
end if;
end loop;
return N;
end Count;
function Count
(Source : in Wide_String;
Pattern : in Wide_String;
Mapping : in Wide_Maps.Wide_Character_Mapping_Function)
return Natural
is
Mapped_Source : Wide_String (Source'Range);
begin
for J in Source'Range loop
Mapped_Source (J) := Mapping (Source (J));
end loop;
return Count (Mapped_Source, Pattern);
end Count;
function Count (Source : in Wide_String;
Set : in Wide_Maps.Wide_Character_Set)
return Natural
is
N : Natural := 0;
begin
for J in Source'Range loop
if Is_In (Source (J), Set) then
N := N + 1;
end if;
end loop;
return N;
end Count;
----------------
-- Find_Token --
----------------
procedure Find_Token
(Source : in Wide_String;
Set : in Wide_Maps.Wide_Character_Set;
Test : in Membership;
First : out Positive;
Last : out Natural)
is
begin
for J in Source'Range loop
if Belongs (Source (J), Set, Test) then
First := J;
for K in J + 1 .. Source'Last loop
if not Belongs (Source (K), Set, Test) then
Last := K - 1;
return;
end if;
end loop;
-- Here if J indexes 1st char of token, and all chars
-- after J are in the token
Last := Source'Last;
return;
end if;
end loop;
-- Here if no token found
First := Source'First;
Last := 0;
end Find_Token;
-----------
-- Index --
-----------
function Index
(Source : in Wide_String;
Pattern : in Wide_String;
Going : in Direction := Forward;
Mapping : in Wide_Maps.Wide_Character_Mapping := Wide_Maps.Identity)
return Natural
is
begin
if Pattern = "" then
raise Pattern_Error;
end if;
-- Handle the case of non-identity mappings by creating a mapped
-- string and making a recursive call using the identity mapping
-- on this mapped string.
if Mapping /= Identity then
declare
Mapped_Source : Wide_String (Source'Range);
begin
for J in Source'Range loop
Mapped_Source (J) := Value (Mapping, Source (J));
end loop;
return Index (Mapped_Source, Pattern, Going);
end;
end if;
if Going = Forward then
for J in Source'First .. Source'Last - Pattern'Length + 1 loop
if Pattern = Source (J .. J + Pattern'Length - 1) then
return J;
end if;
end loop;
else -- Going = Backward
for J in reverse Source'First .. Source'Last - Pattern'Length + 1 loop
if Pattern = Source (J .. J + Pattern'Length - 1) then
return J;
end if;
end loop;
end if;
-- Fall through if no match found. Note that the loops are skipped
-- completely in the case of the pattern being longer than the source.
return 0;
end Index;
-----------
-- Index --
-----------
function Index
(Source : in Wide_String;
Pattern : in Wide_String;
Going : in Direction := Forward;
Mapping : in Wide_Maps.Wide_Character_Mapping_Function)
return Natural
is
Mapped_Source : Wide_String (Source'Range);
begin
for J in Source'Range loop
Mapped_Source (J) := Mapping (Source (J));
end loop;
return Index (Mapped_Source, Pattern, Going);
end Index;
function Index
(Source : in Wide_String;
Set : in Wide_Maps.Wide_Character_Set;
Test : in Membership := Inside;
Going : in Direction := Forward)
return Natural
is
begin
if Going = Forward then
for J in Source'Range loop
if Belongs (Source (J), Set, Test) then
return J;
end if;
end loop;
else -- Going = Backward
for J in reverse Source'Range loop
if Belongs (Source (J), Set, Test) then
return J;
end if;
end loop;
end if;
-- Fall through if no match
return 0;
end Index;
---------------------
-- Index_Non_Blank --
---------------------
function Index_Non_Blank
(Source : in Wide_String;
Going : in Direction := Forward)
return Natural
is
begin
if Going = Forward then
for J in Source'Range loop
if Source (J) /= Wide_Space then
return J;
end if;
end loop;
else -- Going = Backward
for J in reverse Source'Range loop
if Source (J) /= Wide_Space then
return J;
end if;
end loop;
end if;
-- Fall through if no match
return 0;
end Index_Non_Blank;
end Ada.Strings.Wide_Search;