diff --git a/src/ce_common.pas b/src/ce_common.pas
index 66ddd83a..b6c718c4 100644
--- a/src/ce_common.pas
+++ b/src/ce_common.pas
@@ -31,7 +31,7 @@ type
 
   TCECompiler = (dmd, gdc, ldc);
 
-  // function used as hash in gXXX sets & maps
+  // function used as string hasher in fcl-stl
   TStringHash = class
     class function hash(const key: string; maxBucketsPow2: longint): longint;
   end;
@@ -39,12 +39,16 @@ type
   // HashMap for TValue by string
   generic TStringHashMap<TValue> = class(specialize THashmap<string, TValue, TStringHash>);
 
-  // function used as objects in gXXX sets & maps
+  // function used as objects haser in fcl-stl
   TObjectHash = class
     class function hash(key: TObject; maxBucketsPow2: longint): longint;
   end;
 
-  generic TObjectHashSet<TValue> = class(specialize THashSet<TValue, TObjectHash>);
+  // HashSet for any object
+  generic TObjectHashSet<TValue: TObject> = class(specialize THashSet<TValue, TObjectHash>);
+
+  // Used instead of TStringList when the usage would mostly be ".IndexOf"
+  TStringHashSet = class(specialize THashSet<string, TStringHash>);
 
   // aliased to get a custom prop inspector
   TCEPathname = type string;
@@ -322,7 +326,7 @@ begin
   {$IFDEF CPU32}
   Result := longint(Pointer(key)) and (maxBucketsPow2 -1);
   {$ELSE}
-  Result := (longInt(Pointer(key)) xor PlongInt(PInteger(&key) + 4)^) and (maxBucketsPow2 -1);
+  Result := longInt(Pointer(key)){ xor PlongInt(PInteger(&key) + 4)^)} and (maxBucketsPow2 -1);
   {$ENDIF}
   {$POP}
 end;
diff --git a/src/ce_dcd.pas b/src/ce_dcd.pas
index 52ab400d..027c8a89 100644
--- a/src/ce_dcd.pas
+++ b/src/ce_dcd.pas
@@ -27,7 +27,7 @@ type
   private
     fTempLines: TStringList;
     fInputSource: string;
-    fImportCache: TStringList;
+    fImportCache: TStringHashSet;
     fPortNum: Word;
     fServerWasRunning: boolean;
     fClient, fServer: TProcess;
@@ -114,7 +114,7 @@ begin
       fServer.Parameters.Add('-p' + intToStr(port));
   end;
   fTempLines := TStringList.Create;
-  fImportCache := TStringList.Create;
+  fImportCache := TStringHashSet.Create;
 
   if fServer.isNotNil then
   begin
@@ -339,8 +339,9 @@ begin
   if not fAvailable then exit;
   if not fServerListening then exit;
   //
-  if fImportCache.IndexOf(aFolder) <> -1 then exit;
-  fImportCache.Add(aFolder);
+  if fImportCache.contains(aFolder) then
+    exit;
+  fImportCache.insert(aFolder);
   fClient.Parameters.Clear;
   fClient.Parameters.Add('-I' + aFolder);
   fClient.Execute;
@@ -357,9 +358,9 @@ begin
   fClient.Parameters.Clear;
   for imp in folders do
   begin
-    if fImportCache.IndexOf(imp) <> -1 then
+    if fImportCache.contains(imp) then
       continue;
-    fImportCache.Add(imp);
+    fImportCache.insert(imp);
     fClient.Parameters.Add('-I' + imp);
   end;
   if fClient.Parameters.Count <> 0 then