Question

In many places in some Apps which I maintain , I’ve found code which uses a try/finally or try/except block in a for loop or if sentence avoiding the use of begin/end

Consider the next code (not production code, just a sample)

{$APPTYPE CONSOLE}

{$R *.res}

uses
  Classes,
  SysUtils;
    
Procedure TestNoBeginEnd;
var
 i   : Integer;
 L1  : TStringList;
begin
    for i := 1 to 10 do
    try
      L1:=TStringList.Create;
      try
        L1.Add('Bar');
        L1.Add(IntToStr(i));
        L1.Add('Foo');
      finally
        Writeln(L1.Text);
        L1.Free;
      end;
    except
      on E: Exception do
        Writeln('Opps '+E.ClassName, ': ', E.Message);
    end;
end;

begin
  try
    TestNoBeginEnd;

  except
    on E: Exception do
      Writeln(E.ClassName, ': ', E.Message);
  end;
  Readln;
end.

The Question, Is considered a bad practice, code smell or exist any drawback using a try/finally or try/except instead of begin/end in delphi?

UPDATE

I’m sorry by the silly sample code, just for clarify the try/finally and try/except doesn’t pretend replace the begin/end , just to avoid to use it (the begin/end) when exist a case when the use of the try/finally or the try/except doesn’t requires a begin/ end.

Answer 1

I personally don’t see the need to add the extra begin..end around a try..finally/except..end, especially when there is little chance of code being added just before the try or certainly after the end.

That being said, the question would be more whether we need systematically a begin..end after a ..do or a ..then even when there is only a single instruction (in your case a try.. instruction).

It’s mostly a question of style and habit, some people prefer to code defensively and systematically put a begin..end, others try to avoid unnecessary lines as much as possible.

When a fair number of lines are involved, I tend to add the begin..end to make the scoping more obvious.

I’d say, use good judgment and see what the chances are that someone (or you) modifying the code later could miss the intended scope.