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JCF2: Use IntegerList as a base for local TIntList.

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git-svn-id: trunk@56393 -
This commit is contained in:
juha 2017-11-13 17:33:33 +00:00
parent 502dc198c0
commit ce074563bb
1 changed files with 4 additions and 76 deletions
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80
components/jcf2/Utils/IntList.pas
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@ -29,14 +29,7 @@ unit IntList;
A old concept, and a generic class
implemented here because I needed it in the LineBreaker
The internals are a hack, but so what?
They are internal & could be replaced if need be by a more
readable & less space-efficient implementation without anyone knowing
and changing not much code in this unit either.
anyway it works because a pointer = 4 bytes, an int = 4 bytes
Thus a pointer in a TList can actually store an int
If these sizes change, this will break
* Change by JuMa to use TIntegerList from LazUtils as a base class. *
This class could be extended in mnay ways (e.g. math ops on the list like sum, min, max, avg etc)
Fns to add without duplicates, Sort, add another int list (and intersection, difference) etc
@ -48,88 +41,23 @@ unit IntList;
interface
uses Classes, SysUtils;
uses Classes, SysUtils, IntegerList;
type
TIntList = class
private
fcList: TList;
function GetItem(const piIndex: integer): integer;
procedure SetItem(const piIndex, piValue: integer);
protected
TIntList = class(TIntegerList)
public
constructor Create;
destructor Destroy; override;
function Count: integer;
function Add(const piValue: integer): integer;
procedure Clear;
procedure ChangeValue(const liIndex, liDelta: integer);
function IndexOfMax: integer;
{ to use it as a stack }
function Top: integer;
function Pop: integer;
property Items[const piIndex: integer]: integer Read GetItem Write SetItem;
end;
implementation
{$ifndef fpc}
// Delphi is a 32bit compiler only, thus pointer is always uses 4 bytes and can be
// converted to integer and back. FPC uses PtrInt as a signed integer type wich
// equal to pointer in length. For 32bit PtrInt = integer
type
PtrInt = Integer;
{$endif}
{ TIntList }
constructor TIntList.Create;
begin
inherited;
fcList := TList.Create;
end;
destructor TIntList.Destroy;
begin
FreeAndNil(fcList);
inherited;
end;
function TIntList.Add(const piValue: integer): integer;
begin
Result := fcList.Add({%H-}Pointer(PtrInt(piValue)));
end;
procedure TIntList.Clear;
begin
fcList.Clear;
end;
function TIntList.Count: integer;
begin
Result := fcList.Count;
end;
function TIntList.GetItem(const piIndex: integer): integer;
begin
Result := integer({%H-}PtrInt(fcList.Items[piIndex]));
end;
procedure TIntList.SetItem(const piIndex, piValue: integer);
begin
fcList.Items[piIndex] := {%H-}Pointer(PtrInt(piValue));
end;
procedure TIntList.ChangeValue(const liIndex, liDelta: integer);
begin
{ can fall out of bounds, easiest to ignore it here }
@ -166,7 +94,7 @@ begin
if Count > 0 then
begin
Result := Items[Count - 1];
fcList.Delete(Count - 1);
Delete(Count - 1);
end
else
Result := 0;