diff --git a/components/tachart/tachartutils.pas b/components/tachart/tachartutils.pas
index 10b1e1e909..8e6b2c66b9 100644
--- a/components/tachart/tachartutils.pas
+++ b/components/tachart/tachartutils.pas
@@ -130,6 +130,15 @@ type
 
   TShowMessageProc = procedure (const AMsg: String);
 
+  {$IFNDEF fpdoc} // Workaround for issue #18549.
+  generic TTypedFPListEnumerator<T> = class(TFPListEnumerator)
+  {$ELSE}
+  TTypedFPListEnumerator = class(TFPListEnumerator)
+  {$ENDIF}
+    function GetCurrent: T;
+    property Current: T read GetCurrent;
+  end;
+
   { TIndexedComponentList }
 
   TIndexedComponentList = class(TFPList)
@@ -427,6 +436,13 @@ begin
   Result := (A.Code = B.Code) and (A.Data = B.Data);
 end;
 
+{ TTypedFPListEnumerator }
+
+function TTypedFPListEnumerator.GetCurrent: T;
+begin
+  Result := T(inherited GetCurrent);
+end;
+
 { TIndexedComponentList }
 
 procedure TIndexedComponentList.ChangeNamePrefix(
@@ -607,19 +623,19 @@ end;
 
 procedure TBroadcaster.Broadcast(ASender: TObject);
 var
-  i: Integer;
+  p: Pointer;
 begin
   if Locked then exit;
-  for i := 0 to Count - 1 do
-    TListener(Items[i]).Notify(ASender);
+  for p in Self do
+    TListener(p).Notify(ASender);
 end;
 
 destructor TBroadcaster.Destroy;
 var
-  i: Integer;
+  p: Pointer;
 begin
-  for i := 0 to Count - 1 do
-    TListener(Items[i]).Forget;
+  for p in Self do
+    TListener(p).Forget;
   inherited;
 end;
 
diff --git a/components/tachart/tatools.pas b/components/tachart/tatools.pas
index 14512b077a..4c226fab67 100644
--- a/components/tachart/tatools.pas
+++ b/components/tachart/tatools.pas
@@ -1180,25 +1180,24 @@ end;
 
 function TDataPointTool.ParseAffectedSeries: TBooleanDynArray;
 var
-  s: TStringList;
-  i, p: Integer;
+  sl: TStringList;
+  p: Integer;
+  s: String;
 begin
   SetLength(Result, FChart.SeriesCount);
   if AffectedSeries = '' then begin
     FillChar(Result[0], Length(Result), true);
     exit;
   end;
-  s := TStringList.Create;
+  sl := TStringList.Create;
   try
-    s.CommaText := AffectedSeries;
+    sl.CommaText := AffectedSeries;
     FillChar(Result[0], Length(Result), false);
-    for i := 0 to s.Count - 1 do begin
-      p := StrToIntDef(s[i], -1);
-      if InRange(p, 0, High(Result)) then
+    for s in sl do
+      if TryStrToInt(s, p) and InRange(p, 0, High(Result)) then
         Result[p] := true;
-    end;
   finally
-    s.Free;
+    sl.Free;
   end;
 end;
 
diff --git a/components/tachart/tatransformations.pas b/components/tachart/tatransformations.pas
index bf7225ed25..bda62b85f2 100644
--- a/components/tachart/tatransformations.pas
+++ b/components/tachart/tatransformations.pas
@@ -70,7 +70,13 @@ type
 
   TAxisTransformClass = class of TAxisTransform;
 
+  {$IFNDEF fpdoc} // Workaround for issue #18549.
+  TAxisTransformEnumerator = specialize TTypedFPListEnumerator<TAxisTransform>;
+  {$ENDIF}
+
   TAxisTransformList = class(TIndexedComponentList)
+  public
+    function GetEnumerator: TAxisTransformEnumerator;
   end;
 
   { TChartAxisTransformations }
@@ -258,6 +264,13 @@ begin
   AxisTransformsClassRegistry.AddObject(ACaption, TObject(AAxisTransformClass));
 end;
 
+{ TAxisTransformList }
+
+function TAxisTransformList.GetEnumerator: TAxisTransformEnumerator;
+begin
+  Result := TAxisTransformEnumerator.Create(Self);
+end;
+
 { TAxisTransformsComponentEditor }
 
 function TAxisTransformsComponentEditor.GetVerb(Index: Integer): string;
@@ -450,23 +463,21 @@ end;
 
 function TChartAxisTransformations.AxisToGraph(AX: Double): Double;
 var
-  i: Integer;
+  t: TAxisTransform;
 begin
   Result := AX;
-  for i := 0 to List.Count - 1 do
-    with TAxisTransform(List[i]) do
-      if Enabled then
-        Result := AxisToGraph(Result);
+  for t in List do
+    if t.Enabled then
+      Result := t.AxisToGraph(Result);
 end;
 
 procedure TChartAxisTransformations.ClearBounds;
 var
-  i: Integer;
+  t: TAxisTransform;
 begin
-  for i := List.Count - 1 downto 0 do
-    with TAxisTransform(List[i]) do
-      if Enabled then
-        ClearBounds;
+  for t in List do
+    if t.Enabled then
+      t.ClearBounds;
 end;
 
 constructor TChartAxisTransformations.Create(AOwner: TComponent);
@@ -488,11 +499,11 @@ end;
 procedure TChartAxisTransformations.GetChildren(
   Proc: TGetChildProc; Root: TComponent);
 var
-  i: Integer;
+  t: TAxisTransform;
 begin
-  for i := 0 to List.Count - 1 do
-    if TAxisTransform(List[i]).Owner = Root then
-      Proc(TAxisTransform(List[i]));
+  for t in List do
+    if t.Owner = Root then
+      Proc(t);
 end;
 
 function TChartAxisTransformations.GraphToAxis(AX: Double): Double;
@@ -508,12 +519,11 @@ end;
 
 procedure TChartAxisTransformations.SetChart(AChart: TObject);
 var
-  i: Integer;
+  t: TAxisTransform;
 begin
-  for i := 0 to List.Count - 1 do
-    with TAxisTransform(List[i]) do
-      if Enabled then
-        TAxisTransform(List[i]).SetChart(AChart);
+  for t in List do
+    if t.Enabled then
+      t.SetChart(AChart);
 end;
 
 procedure TChartAxisTransformations.SetChildOrder(
@@ -539,12 +549,11 @@ end;
 
 procedure TChartAxisTransformations.UpdateBounds(var AMin, AMax: Double);
 var
-  i: Integer;
+  t: TAxisTransform;
 begin
-  for i := 0 to List.Count - 1 do
-    with TAxisTransform(List[i]) do
-      if Enabled then
-        UpdateBounds(AMin, AMax);
+  for t in List do
+    if t.Enabled then
+      t.UpdateBounds(AMin, AMax);
 end;
 
 { TLinearAxisTransform }