pyscripter

This is now fixed.  @acalandCould you please report whether fpc MacOS works ok?

2 hours ago, BennieC said:

@pyscripter

I have used your structure but still Delphi insist on giving me strings instead of floating point values.

Can I somehow force the variant conversion to take this as a float?  I have tried to assign the variant to single variable but have no luck.

Regards

 

Variants are converted to strings when shown in the debugger.  It does not mean that they contain strings.

2 hours ago, BennieC said:

Value: (array([[0.09, 0.03, 0.34...0.]]. dtype=float32), array([[0.06, 0.05, 0.67...0.]]. dtype=float32))

Currently this is just returned as a value with name layerOutputs, but Delphi sees this as a character string

No it does not.   You get a tuple containing arrays of floating type values.   Are you using VarPyth? Is layerOutputs a Variant?

If yes then you can use:

var arr:Variant := layerOutputs.GetItem(0);  // the first item of the tupple (array).
var value:Variant := arr.GetItem(0);  //the first floating value of the array

By the way and on record helpers, in my little program above,  if you move the declaration

var
  Rec: MyRec;

to Unit 1, interestingly, the output is "Hi".

6 minutes ago, Vincent Parrett said:

If that were the case, then you wouln't need to change anything at all in SynEdit - but you do as it cannot see SetAdditionalPCREOptions.

The issue was in the following:

procedure TRegExHelper.AddRawOptions(PCREOptions: Integer);
begin
  with Self do FRegEx.SetAdditionalPCREOptions (PCREOptions);
end;

FRegEx is defined in System.RegularExpressions and the nearest helper was in that unit.

By the way the issue is now fixed.  Thanks for reporting it.

25 minutes ago, Vincent Parrett said:

The one that embarcadero created will be used first, the synedit one will be ignored. Which helper is used is dependant on where they are decleared, since embarcadero declared theirs closest to the actual class declaration theirs will be seen first rather than the one on synedit. 

Actually it is the other way round.   From the docs:

Quote

You can define and associate multiple helpers with a single type. However, only zero or one helper applies in any specific location in source code. The helper defined in the nearest scope will apply. Class or record helper scope is determined in the normal Delphi fashion (for example, right to left in the unit's uses clause).

but "nearest scope" means closer to where the variable is declared.

Just to prove:

Project File:

program Project1;

{$APPTYPE CONSOLE}

{$R *.res}

uses
  System.SysUtils,
  Unit1 in 'Unit1.pas';

type
  MyRecHelper2 = record helper for MyRec
    procedure SayHi;
  end;

{ MyClassHelper1 }

procedure MyRecHelper2.SayHi;
begin
  WriteLn('Hello!');
end;

var
  Rec: MyRec;

begin
  Rec.SayHi;
  ReadLn;
end.

Unit 1

unit Unit1;

interface

type

  MyRec = record

  end;

  MyRecHelper1 = record helper for MyRec
    procedure SayHi;
  end;

implementation

{ MyClassHelper1 }

procedure MyRecHelper1.SayHi;
begin
  WriteLn('Hi!');
end;

end.

Output:

Hello!

11 minutes ago, Vincent Parrett said:

the best option would be to change SetAdditionalPCREOptions to AddRawOptions - then it will compile in all supported versions.

What happens then in Delphi 11.2?   Which record helper will be active?  I thought you are not allowed to have two helpers for the same class in the same scope?

33 minutes ago, Vincent Parrett said:

Unfortunately they were implemented using a class helper, which now breaks Turbopack/SynEdit

Yes indeed.  Do you know how to IFDEF 11.2 vs 11.1?

Regular Expressions have been revamped. The following feature requests have been implemented:

https://quality.embarcadero.com/browse/RSP-21733

https://quality.embarcadero.com/browse/RSP-22372

https://quality.embarcadero.com/browse/RSP-22381

I am having issues upgrading to 11.2.   I run the Web Installer keeping the registry options.  It appears to be going smoothly , uninstalling the previous version, then showing a message "Installing Main Application files" and in a few seconds it stops with a message "installation finished".

I can see the application files in the Programs directrory, it even installs a shortcut on the desktop.  But at the end of the installation I can see a running process bds.exe, that does nothing.  If I end the process and try to run Rad Studio from the shortcut the bds.exe process starts but nothing happens.

I remember that with previous version upgrades it would ask me for personalities and download tons of stuff from the cloud.   This time nothing of the sort.

Any clues?

Update:  The issue was related to addins.   After removing the references to Beyond Compare, Parnassus and Gexperts, bds.exe started and allowed me to select platforms.   It is now downloading and installing OK.  And it works well.

This is a code fragment that shows you how to convert python strings to Delphi strings with PyArg_ParseTuple

function ShowMessage_Wrapper(pself, args: PPyObject): PPyObject; cdecl;
var
  LMsg: PAnsiChar;
begin
  with GetPythonEngine do
  begin
    if PyArg_ParseTuple(args, 's:ShowMessage', @LMsg) <> 0 then
    begin
      ShowMessage(Utf8ToString(LMsg));
      Result := GetPythonEngine.ReturnNone;
    end else
      Result := nil;
  end;
end;

Also have a look at the PyArg_ParseTuple documentation.

Using such methods is the low level approach to exposing Delphi code to python.    Please have a look at WrapDelphi demos and tutorials for a high-level approach that that does not require you to use PyArg_ParseTuple or worry about reference counting and the like.  

Something like:

var SL := TStringList.Create;
try
  SL.LoadFromFile('__main__.py');
  GetPythonEngine.ExecStrings(SL);
  Mainmodule.run_settings();
finally 
  SL.Free;
end;

You can use LockUndo to disable Undo altogether.

LockUndo/UnlockUndo is also useful when you read a file or initially setup a text buffer.  If the Undo buffer is not empty then you would want to call ClearUndo before or after.

Assuming you are using the Turbopack Synedit:

Changes to the text buffer are undoable.   So just calling Delete does not clear all related memory.    You need to do one of:

• call ClearUndo every now and then to release the undo/redo memory.
• Set MaxUndo to some number to limit the undoable actions.  The default is 0 (unlimited undo/redo).
• call LockUndo/Unlock undo to prevent actions being added to the undo/redo stack (the most efficient).

If you still get a memory overflow then this is a bug that you should report.

I had a similar issue.   If I remember well, setting the ParentBackground property to true for all controls helped, although I see in the previous thread that @Uwe Raabe claimed the opposite.

There was such an issue https://quality.embarcadero.com/browse/RSP-31158 that is supposed to be fixed in D11.   See also the related issues to this one.

See also TStyleManager.UseParentPaintBuffers introduced in D11.   I have not tried it and there is limited documentation.

You are not calling PythonEngine1.Load.
Demo34 shows how to load a python engine dynamically, but please note that this is very tricky and things can go wrong.

Python4Delphi demo33 (multithread) does not work · Issue #373 · pyscripter/python4delphi (github.com) is now fixed.  

TPythonEngine and TPyDelphiWrapper are singleton.  You should not have two in the same application.   Better to add your control wrapper to delphivcl and recompile.

In using delphivcl.pyd  the user can attach an arbitrary python method as an event handler to any vcl component at runtime.   The event handler needs to be created on-the-fly, since you do not know in advance what python method will attach to which events.   TMethodImplementation can do just that.  Create an event handler of the right type when it is need.  In this use case the callback would translate the Args to their python equivalents and call the python code.

The callback can be an anonymous method, but this is not important.  The important thing is that the event handler needs to be created at runtime and not at compile time.  Currently  python4delphi needs to provide helper classes for each event type (TNotifyEventHandler for TNotifyEvent etc.).  All this code can go away and have just one generic implementation of event handling that can deal with any kind of event.

For example in the code below:

class MyForm(Form):
    def __init__(self, owner):
        self.timer = Timer(self)
        self.timer.Interval = 10
        self.timer.OnTimer = self.__on_timer
        self.timer.Enabled = True

    def __on_timer(self, sender):
        self.CheckBox1.Enabled = True

when self.timer.OnTimer = self.__on_timer is executed an event handler needs to be attached to the OnTimer event of a Delphi timer object that will run the python method.

1 hour ago, Dave Novo said:

While technically this seems cool, why is this particularly useful? I see that I can create an event handler without an explicit object that will implement the event handler method. Why would I need to do this?

 

Did you read my first post?  It answers your question providing some use cases.  Spring4d also uses this for supporting multicast events.

Here is an example of making an event handler on the fly using spring4d, TMethodImplementation and a callback routine, in case anyone has a use for it.

program MethodImplementationTest2;
{$APPTYPE CONSOLE}
{$R *.res}

uses
  System.SysUtils,
  System.TypInfo,
  System.Rtti,
  Spring;

type
  TSimpleEvent = function(I: Integer): Integer of object;

  TTestClass = class
  private
    fEvent: TSimpleEvent;
  published
    property Event: TSimpleEvent read fEvent write fEvent;
  end;

procedure ImplCallback(UserData: Pointer; const Args: TArray<TValue>;
    out Result: TValue);
begin
  WriteLn('From Implementation');
  WriteLn(Args[0].AsObject.ClassName);
  Result := Args[1].AsInteger * 2;
end;

begin
  ReportMemoryLeaksOnShutdown := True;
  var TestObj := Shared.Make(TTestClass.Create)();
  try
    var RTTIContext := TRttiContext.Create;
    var RTTIType := RTTIContext.GetType(TypeInfo(TTestClass));
    var RTTIMethodType := RTTIType.GetProperty('Event').PropertyType;

    var MethodImplementation := (RTTIMethodType as TRttiInvokableType).CreateImplementation(nil, ImplCallback);
    var Method: TMethod;
    Method.Code := MethodImplementation.CodeAddress;
    Method.Data := TestObj;
    SetMethodProp(TestObj, 'Event', Method);

    WriteLn(TestObj.Event(2));
    MethodImplementation.Free;
  except
    on E: Exception do
      Writeln(E.ClassName, ': ', E.Message);
  end;
  ReadLn;
end.

Output:

From Implementation
TTestClass
4

Feature request submitted: [RSP-38690] Add CreateImplementation method for TRttiInvokableType - Embarcadero Technologies

System.Rtti contains a lesser known, but powerful class TMethodImplementation, which is basically hidden and used in TVirtualMethodInterceptor.  Outside this use, it cannot be created directly and it can only be accessed by TRttiMethod.CreateImplementation.   

I recently discovered that Spring4d extends its use through a helper for TRttiInvokableType, so it can be used with standalone procedures and functions as well as with events.  Here is a small console app showing how it can be used:

program MethodImplementationTest;
{$APPTYPE CONSOLE}
{$R *.res}

uses
  System.SysUtils,
  System.TypInfo,
  System.Rtti,
  Spring;

type
  TSimpleProc = function(I: Integer): Integer;

procedure ImplCallback(UserData: Pointer; const Args: TArray<TValue>;
    out Result: TValue);
begin
  WriteLn('From Implementation');
  Result := Args[0].AsInteger * 2;
end;

var
  Proc: TSimpleProc;
begin
  ReportMemoryLeaksOnShutdown := True;
  try
    var RTTIContext := TRttiContext.Create;
    var RTTIType := RTTIContext.GetType(TypeInfo(TSimpleProc));
    var ProcImplementation := (RTTIType as TRttiInvokableType).CreateImplementation(nil, ImplCallback);

    Proc := TSimpleProc(ProcImplementation.CodeAddress);

    WriteLn(Proc(2));
    ProcImplementation.Free;
  except
    on E: Exception do
      Writeln(E.ClassName, ': ', E.Message);
  end;
  ReadLn;
end.

Output:

From Implementation
4

Simple and easy.  Spring4D is full of gems.  I wish the above functionality was part of the standard library.

I can think of many uses:

• Python4Delphi contains a unit MethodCallback which uses complex assembly to convert methods into stubs that can be used with external C libraries.  It could be rewritten using TMethodImplementation, without assembly code.
•  Also in Python4Delphi, the implementation of Delphi events using python code could be very much simplified and generalized using TMethodImplementation.  You can create Delphi functions, procedures and methods, event handlers on the fly that are implemented by python code.
• Similarly functionality can be provided with other scripting languages.

This was due to a bug (TPyDelphiObject.SetAttrO causes memory leak · Issue #368 · pyscripter/python4delphi (github.com)) which is now fixed.   

It may take some time for the fix to be reflected in the pip installable delphivcl, but you can always compile your own delphivcl.pyd from the github sources.

@shineworldThanks for discovering the issue.

Just to clarify.   

a)  No memory leakage happens if your timer routine is:

    def __on_timer(self, sender):
        pass

b)  The increase in memory usage increases indefinitely when self.CheckBox1.Enabled = True is called inside the timer routine.

c) Could this be tracemalloc overhead?   (the memory traces take memory space).  For example does the memory gets released with 

tracemalloc.clear_traces()  (tracemalloc — Trace memory allocations — Python 3.10.5 documentation)

d) Do you see Windows memory allocated to the process increasing without tracemalloc