codetools: fixed compilation with fpc<3.1.1

git-svn-id: trunk@54763 -

components/codetools/directorycacher.pas

@@ -293,7 +293,6 @@ function CompareUnitLinkNodes(NodeData1, NodeData2: Pointer): integer;
 function CompareUnitNameWithUnitLinkNode(AUnitName: Pointer;
   NodeData: pointer): integer;
 
-
 implementation
 
 const
@@ -539,6 +538,43 @@ begin
   Result:=CompareText(String(AUnitName),TUnitFileNameLink(NodeData).Unit_Name);
 end;
 
+{$IF FPC_FULLVERSION<30101}
+function IsValidIdent(const Ident: string; AllowDots: Boolean = False; StrictDots: Boolean = False): Boolean;
+const
+  Alpha = ['A'..'Z', 'a'..'z', '_'];
+  AlphaNum = Alpha + ['0'..'9'];
+  Dot = '.';
+var
+  First: Boolean;
+  I, Len: Integer;
+begin
+  Len := Length(Ident);
+  if Len < 1 then
+    Exit(False);
+  First := True;
+  for I := 1 to Len do
+  begin
+    if First then
+    begin
+      Result := Ident[I] in Alpha;
+      First := False;
+    end
+    else if AllowDots and (Ident[I] = Dot) then
+    begin
+      if StrictDots then
+      begin
+        Result := I < Len;
+        First := True;
+      end;
+    end
+    else
+      Result := Ident[I] in AlphaNum;
+    if not Result then
+      Break;
+  end;
+end;
+{$ENDIF}
+
 { TCTDirectoryCache }
 
 function TCTDirectoryCache.GetStrings(const AStringType: TCTDirCacheString