TStringBuilder not found but TAnsiStringBuilder found?

[fafafooey]

Hey all, I was messing around with adding verbose logging to my app which would save the lines to a file if an error occurred. I was deciding between TStringList and TStringBuilder but something weird is going on with TStringBuilder. I can only see TAnsiStringBuilder in the identifier completion window but not TStringBuilder. I'm using Lazarus x86 2.2.4, FPC 3.2.2 on Windows 7. This is a windows program in Delphi mode and I have SysUtils in the uses. I think it should be in there since "TStringBuilder = TAnsiStringBuilder" is declared and included in SysUtils. I can't even do "SysUtils.TStringBuilder". What am I not seeing that is preventing TStringBuilder from being declared as a variable?

Thanks for your help in advance!

[TRon]

First thing that comes to mind is that Lazarus is unable to find the Free Pascal RTL source-files. Have you configured that correctly ? fwiw that is only a problem with code-tools if you insist by typing the name manually then it should compile.

[fafafooey]

Thanks for the reply TRon. My "FPC source directory" in IDE Options -> Environment -> Files is set to the correct FPC source directory. I did this below:

procedure TForm1.FormCreate(Sender: TObject);
var
  x: TStringBuilder;
  y: TAnsiStringBuilder;

begin

  x := TStringBuilder.Create;

  x.Append('Hello');

  y := TAnsiStringBuilder.Create;

  y.Append('Hello');

end;

It compiles fine but the code completion window only shows the following 2 entries:

TAnsiStringBuilder = class
TUnicodeStringBuilder = TAnsiStringBuilder

I'm expecting TStringBuilder to show, right? Does anyone else's Laz 2.2.4 x86 show TStringBuilder or is it like mine?

Thanks!

[wp]

When I Ctrl+click on "TAnsiStringBuilder" in your code, the IDE opens the file "sysstrh.inc" (in the fpc source folders) and it shows:

Code: Pascal  [Select][+][-]

1. {$define TStringBuilder:=TAnsiStringBuilder}

This means that there is no separate class TStringBuilder, this identifier is just an alias for "TAnsiStringBuilder".

[fafafooey]

Thanks for the reply wp. Yea I saw that too in "sysstrh.inc" but there is also "{$undef TStringBuilder}" before "Type  TStringBuilder = TAnsiStringBuilder;". So I thought there would be a TStringBuilder type in the code completion window. I'm not an expert on compiler defines at all though so if this is the expected behavior then no problem.

I added "TStringBuilder = TAnsiStringBuilder;" under the TForm1 class and the code completion window shows it and the x: TStringBuilder var shows all the TAnsiStringBuilder functions as expected. I just thought TStringBuilder was already a declared type because of that last line in "sysstrh.inc".

Thanks

[PascalDragon]

Code: Pascal  [Select][+][-]

1. {$define TStringBuilder:=TAnsiStringBuilder}

This means that there is no separate class TStringBuilder, this identifier is just an alias for "TAnsiStringBuilder".

To be more precise: the define is used for the include file which includes a generic implementation for both TAnsiStringBuilder and TUnicodeStringBuilder where TStringBuilder is used as a placeholder (macros don't work across units). So no, there does not exist a TStringBuilder class.

[fafafooey]

Thanks for the reply PascalDragon. I was looking in the FPC source on gitlab and I see these commits for sysstrh.inc, syssbh.inc and syssb.inc:

{$define TGenericStringBuilder:=TAnsiStringBuilder}

TGenericStringBuilder = class

* rename generic TStringBuilder to TGenericStringBuilder to make code tools happy

Does this mean TStringBuilder will show as a type in the code completion window in the current version of FPC?

Thanks!

[PascalDragon]

Does this mean TStringBuilder will show as a type in the code completion window in the current version of FPC?

The important part is the type alias in line 339 of sysstrh.inc. It's simply that Lazarus CodeTools had/has problems if there is a temporary define with the same name in the same unit which is why that was changed. So yes, with the current version of FPC there shouldn't be a problem anymore.

[fafafooey]

Ok thanks PascalDragon, my eyes were hurting trying to figure out why I wasn't seeing TStringBuilder. The next version of FPC is looking great btw, great job on it!