[DUG] O.o hmmm ok

[Judd, Struan (eCargo)]

Records are constructs with Value semantics whereas Objects have
Reference semantics.

This means that in the following code is the Assignment 1 and Assignment
2 are semantically identical:

Var a, b: record
	name: String;
	age: Integer;
	end;

Begin
	a.name := 'Me';
	a.age := 39;

//	Assignment 1
	b := a;

//	Assignment 2
	b.name := a.name;
	b.age := a.age;
End;

TTFN, Struan.

Nick wrote:
> Got something weird here - weird because I probably don't understand
> it properly but it caused me a bit of delay... Simplified, I had a
> global array of records, during my procedure I would do something
> like this  
> 
> PRec := MyArrayofPRec[0];
> PRec.name := 'Hi';
> 
> Now for some reason I was expecting MyArrayOfPRec[0].name to be now
> 'Hi' 
> as well, but it's not.
> 
> Here is an example that I whipped up just now which lead me to expect
> this. 
> 
> type
>   TMyRec = Record
>     name : string;
>   end;
> 
> 
> var
>   Form1: TForm1;
>   TTH : TMyRec;
> 
> procedure TForm1.FormCreate(Sender: TObject); begin
>   TTH.name := 'BoB';
> end;
> 
> procedure TForm1.Button1Click(Sender: TObject); var
>   t : TMemo;
>   b : TMyRec;
> begin
>   t := Memo1;
>   t.lines.add('hi');
> 
>   b := TTH;
>   b.name := 'Smile';
>   t.lines.add(TTH.name);
> end;
> 
> Now in this example when it's ran and button 1 is clicked - Hi is
> added to the Memo1 and Bob is added. 
> So why can I assign Memo1 to T and all actions done to T are done to
> Memo1, but the same isn't with the Record. 
> Is it because Record isn't from TObject?
> I guess it's like
> var
>     a,b : integer;
> begin
>     a := 1;
>     b := a;
>     b := 10; //a still = 1 which is what I would expect end;
> 
> so is it because TMemo is an Object and the record and a,b above are
> just variables? 
> 
> O.o
> Thanks
> 
> 
> 
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