Friend in Delphi

[sggaunt]

I am soon going to be teaching some OOP concepts at College, unfortunatly I must use Borland C++ (4.5), can anyone help with a translatikon of how this relates to Delphi, so I can get a better understanding of whats going on.

C++ has 'friend' declaration, looks a bit like a 'public' declaration in Delphi.
The info I have is

A Friend functionm is a non-member function which is allowed access to the private data

Public right?
the example I have looks like this

class Complex
{
// list of friend functions
friend float add_real(Complex&, Complex&);
private
  float, real, imag;
public
 Complex(float,float);
}

Is there some sort of pre declaration going on here (because C is low level rubbish) or what.
Please, no-one suggest the C++ forum, been there, dont want to go again.


Steve: N.M.N.F.
If something is popular, it must be wrong: Mark Twain

 

[DjangMan]

Can't get the Turbo versions of Delphi approved/installed?

 

[Glenn9999]

This may be helpful.

http://www.desy.de/gna/html/cc/Tutorial/tutorial.html

It is not possible for anyone to acknowledge truth when their salary depends on them not doing it.

 

[sggaunt]

Good idea Djangman, the problem is that they (The students) have already been using C++ (only the C aspects) since September.
I am taking over for the Planning and 'Basic OOP' bits of the course.
Trying to find out if the 'friend' thing is something you must do in C++ to make a function public. Because the students are at NQF level 3 (UK) they dont need a lot of high end stuff. So if they dont need 'friend' explaining I wont, you get the idea?
Love to show them the Delphi (object Pascal) model, but then they cannot try any code snippets.
I do have some C++ examples from when I did it at Uni.


Steve: N.M.N.F.
If something is popular, it must be wrong: Mark Twain

 

[TonHu]

Friend classes are allowed access to other classes private/protected stuff. If they should be public, then define them as public.

 

[sggaunt]

Ok thanks TonHu, that plus a bit of googling, reveals that you can set up a simple class without 'friend' as I said this is for 'learners' (me included) I need to keep it simple.


Steve: N.M.N.F.
If something is popular, it must be wrong: Mark Twain

 

[djjd47130]

I wish I knew more, I'm actually cross-working between Delphi and C# (in ASP.NET). First of all I know I could get Delphi.net now, but that's another story. I've been converting much of my previous delphi classes (OOP) into C# and I'm about as frustrated as you... For example a database table wrapper I built in D7 - in the end, it uses the exact same properties and such, just structured entirely different. I think you need to start teaching code conversion using OOP I wrote an article a while back here about OOP:

http://tek-tips.com/viewthread.cfm?qid=1626218&page=1

JD Solutions

 

[sggaunt]

Monday I will take them back over the stuff they need to be clear on, before they can start on OOP.
Structured programming(functions), Modularity, Structures(Records), etc.
I found some simple OOP tutorials on the web, should suffice for what I need.

Steve: N.M.N.F.
If something is popular, it must be wrong: Mark Twain

 

[MagicFrisbee]

I did Delphi and C/C++ in college. A friend allows instances of a friended class to see normally hidden methods and properties. To all classes that aren't friends of that class, they can't see those same methods and properties. C does have a public declaration if I remember correctly.

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