learn C++ or C#

[Larry Smith]

Re: learn C++ or C#

Multi-threading, GUI development is much easier in most of the other

languages compared to the efforts you have to take in C++, because they
support it out of the box. Fortunately C++ has Boost.

To be fair, this has nothing to do with C++ as a language (which has no
support for multi-threading or GUI whatsoever). You have to separate the
tools from the language itself.

The only programming paradigm I miss in the other languages is RAII.
That's IMHO still a big plus of C++.

RAII is also vastly superior to "IDispose" and "using" statements. OTOH,
..NET advocates will point out that the GC takes care of cleaning most
resources so the programmer has to do nothing at all. IMO the C++ paradigm
is still a better design but the reasons run too deep to get into here.

A simple example:
>
How do I ensure in C++ that I have successfully overridden a base class
virtual function and that the compiler throws an error if the base class
implementation has changed ?

C++ has many warts, many a legacy of C itself. From cast issues (very
dangerous) to forgetting to handle newly added class members in your
existing copy constructors and copy assignment operators. Templates are also
an incredible source of difficulty and potential errors (very difficult to
understand, read, and get right beyond the basics - some things will be
improving in C++0x but it's really too late). The use of #includes and
headers in general (from C) is also a hornets nest of serious problems. Not
to mention the usual issues of pointer handling, the cryptic nature of the
syntax itself (from C style arrays to function pointers to many types of
arcane C++ constructs like binders, adapters, etc. - did I mention
templates?). The dizzying array of rules and trap doors in general is very
difficult to master.

I also have some serious pet peeves. Why didn't they permit local classes to
be passed as template arguments. I once asked Stroustrup about this at a
conference but I wasn't satisfied with his terse response. The fact is that
many templates are useful for small local tasks. Why should I use the
"for_each" template for instance (among many others) if the tiny function
object I want to pass has to be declared outside the function itself (where
I'm using "for_each") . It would be so much cleaner to just declare the
function object locally. C# allows me to use anonymous methods which is so
much cleaner. The issues surrounding C++ go on and on.

Don't get me wrong, C++ is still a very powerful and flexible language with
incredible versatility (and very elegant design constructs in spite of all
the problems). The trade-off is that it's very difficult to master and
therefore prone to many serious problems. Even very experienced developers
have to continuously bend their minds out of shape and remain on guard years
after learning the language. This is not the hallmark of a successful
language in spite of C++'s "stellar" reputation and the millions who
continue struggling with it.

[Giovanni Dicanio]

Re: learn C++ or C#


[Larry Smith]

>The only programming paradigm I miss in the other languages is RAII.
>That's IMHO still a big plus of C++.

>
RAII is also vastly superior to "IDispose" and "using" statements. OTOH,
.NET advocates will point out that the GC takes care of cleaning most
resources so the programmer has to do nothing at all.

The GC is fine for memory resources - it runs a garbage collection process
when under memory pressure.
But, what about non-memory resources (like sockets, textures, files, etc.) ?
I think that GC is designed for memory resources only, and has very little
clue about non-memory resources.

Instead, if you use RAII and a smart pointer (like shared_ptr, or some
intrusive reference count smart pointer) to manage non-memory resources,
they will be released as soon as the ref count becomes 0, making a very
efficient use of precious resources.

Yes, C# is a very well designed language, which incorporates lots of lessons
learned from C++, Java and Visual Basic.
But C# has not discovered destructors yet :)

Giovanni

[Larry Smith]

Re: learn C++ or C#

The GC is fine for memory resources - it runs a garbage collection process

when under memory pressure.
But, what about non-memory resources (like sockets, textures, files, etc.)
?
I think that GC is designed for memory resources only, and has very little
clue about non-memory resources.

Yes, that's what "IDisposabl e" is for as previously mentioned. The "using"
statement is just a compiler-generated wrapper around it, putting your code
in a "try/finally block behind the scenes and calling
"IDisposable.Di spose()" for you. RAII is clearly much better than this.

Instead, if you use RAII and a smart pointer (like shared_ptr, or some
intrusive reference count smart pointer) to manage non-memory resources,
they will be released as soon as the ref count becomes 0, making a very
efficient use of precious resources.
>
Yes, C# is a very well designed language, which incorporates lots of
lessons learned from C++, Java and Visual Basic.
But C# has not discovered destructors yet :)

Actually it has destructors but they're not the same as C++ destructors
(they're just compiler-generated wrappers for "Object.Finaliz e()"). I
already agree that object creation/destruction in C++ is cleaner and more
natural IMO. This hardly makes up for the many problems in C++ however. Like
many others, I have a love/hate relationship with it but objectively
speaking (IMO anyway), it's still a failure for the reasons I mentioned
previously.

[Andre Kaufmann]

Re: learn C++ or C#

Larry Smith wrote:

>Multi-threading, GUI development is much easier in most of the other
>languages compared to the efforts you have to take in C++, because they
>support it out of the box. Fortunately C++ has Boost.

>
To be fair, this has nothing to do with C++ as a language (which has no
support for multi-threading or GUI whatsoever). You have to separate the
tools from the language itself.

I don't think so. What would C++ be without the standard library ?

And that GUI development is easier in other languages has IMHO something
to do with the language. C++ isn't IMHO fast enough in compilation to be
a good RAD language - at least you don't have the same developing
experience in C++ as in other languages.

[...]
RAII is also vastly superior to "IDispose" and "using" statements. OTOH,

Yes. Using is fine if I hold a resource in a control block, but if the
resource is held by let's say multiple lists, I have to use some kind of
smart pointers to handle the resources efficiently. In C# I can rely on
the GC to free the memory - so far that's fine. But resources should be
freed immediately, if they aren't used anymore.

.NET advocates will point out that the GC takes care of cleaning most
resources so the programmer has to do nothing at all. IMO the C++ paradigm
is still a better design but the reasons run too deep to get into here.
>
>
[...]
understand, read, and get right beyond the basics - some things will be
improving in C++0x but it's really too late). The use of #includes and
headers in general (from C) is also a hornets nest of serious problems. Not

I don't think that it's too late, C++ modules could fix many problems.
But since they aren't in the upcoming standard I perhaps have to agree -
it will be too late.

[...]

Andre

[Peter Duniho]

Re: learn C++ or C#

On Thu, 24 Jul 2008 06:43:30 -0700, Giovanni Dicanio
<gdicanio@_nosp am_email_dot_it wrote:

[Larry Smith]
>

>>The only programming paradigm I miss in the other languages is RAII.
>>That's IMHO still a big plus of C++.

>>
>RAII is also vastly superior to "IDispose" and "using" statements. OTOH,
>.NET advocates will point out that the GC takes care of cleaning most
>resources so the programmer has to do nothing at all.

>
The GC is fine for memory resources - it runs a garbage collection
process
when under memory pressure.
But, what about non-memory resources (like sockets, textures, files,
etc.) ?
I think that GC is designed for memory resources only, and has very
little
clue about non-memory resources.

This distinction has nothing to do with the _language_. If the OS was
entirely garbage collected, then these "non-memory resources" wouldn't be
an issue. They would be managed the same way memory is in .NET and you'd
never have to worry about disposing them.

Now, with certain types of objects you'd still have to deal with closing,
flushing, etc. But that's not something that RAII inherently solves; it
just happens that C++ classes can take advantage of that to handle those
operations. The OS API itself isn't based on C++ and requires the program
to deal with managing those operations.

In C++, RAII provides a convenient way to deal with that, and in C#, the
"using" statement does the same. You may prefer one syntax over the
other, but I personally don't see a difference between the two that would
justify an argument of superiority one way or the other. Larry's claim of
"vastly superior" seems particularly baseless. Vastly? Pure hyperbole.

Pete

[Larry Smith]

Re: learn C++ or C#

>>Multi-threading, GUI development is much easier in most of the other

>>languages compared to the efforts you have to take in C++, because they
>>support it out of the box. Fortunately C++ has Boost.

>>
>To be fair, this has nothing to do with C++ as a language (which has no
>support for multi-threading or GUI whatsoever). You have to separate the
>tools from the language itself.

>
I don't think so. What would C++ be without the standard library ?

It would be another language since it must include the library by
definition. Contrast this to C# whose basic support is primitive (see the
standard for yourself). In any case, the claim that GUI development is
"easier" in C# compared to C++ has nothing to do with the languages
themselves. It's the rich set of classes in MSFT's framework combined with
better development tools that make C# easier (noting that C# is a natural
fit for the framework unlike C++). Provide an equivalent C++ library and
better tools and it will be just as easy (not taking into account the actual
language differences).

And that GUI development is easier in other languages has IMHO something
to do with the language. C++ isn't IMHO fast enough in compilation to be a
good RAD language - at least you don't have the same developing experience
in C++ as in other languages.
>

>[...]
>RAII is also vastly superior to "IDispose" and "using" statements. OTOH,

>
Yes. Using is fine if I hold a resource in a control block, but if the
resource is held by let's say multiple lists, I have to use some kind of
smart pointers to handle the resources efficiently. In C# I can rely on
the GC to free the memory - so far that's fine. But resources should be
freed immediately, if they aren't used anymore.

The "using" statement is ugly compared to RAII. Moreover, in theory your
unmanaged resources may never be released if you neglect to call
"IDisposable.Di spose()". Other problems also exist with this pattern.

>

>.NET advocates will point out that the GC takes care of cleaning most
>resources so the programmer has to do nothing at all. IMO the C++
>paradigm
>is still a better design but the reasons run too deep to get into here.
>>
>[...]
>understand, read, and get right beyond the basics - some things will be
>improving in C++0x but it's really too late). The use of #includes and
>headers in general (from C) is also a hornets nest of serious problems.
>Not

>
I don't think that it's too late, C++ modules could fix many problems. But
since they aren't in the upcoming standard I perhaps have to agree - it
will be too late.

The core language is in place. Enhancements won't change that. The problems
inherent in C++ will remain forever unless it morphs into a different
language (but then it won't be C++ anymore).

[Giovanni Dicanio]

Re: learn C++ or C#


"Peter Duniho"

In C++, RAII provides a convenient way to deal with that, and in C#, the
"using" statement does the same. You may prefer one syntax over the
other, but I personally don't see a difference between the two that would
justify an argument of superiority one way or the other.

Destructor and "scope" syntax in C++ is cleaner, simpler and more elegant
than C# bloated 'using'.

Moreover, there is big difference between C++ RAII and C# "using".

In Andre's words:

<quote>
Using is fine if I hold a resource in a control block, but if the
resource is held by let's say multiple lists, I have to use some kind of
smart pointers to handle the resources efficiently.
</quote>

For example: I think that there is nothing like shared_ptr in C#.
With shared_ptr you can have a *deterministic* resource manager, and you can
wrap also non-memory resources in classes and store shared_ptr to these
class instances into STL containers, and that works fine and is very elegant
and simple.

And there are also intrusive smart pointers, you may consider Eugene
Gershink's implementation here:

http://www.gershnik.com/articles/refcnt_ptr.asp

BTW: I'd like to make it clear that I'm saying neither that C++ is better
than C#, nor that C# is better than C++. Simply, both languages have pros
and cons.

Giovanni

[Larry Smith]

Re: learn C++ or C#

In C++, RAII provides a convenient way to deal with that, and in C#, the

"using" statement does the same. You may prefer one syntax over the
other, but I personally don't see a difference between the two that would
justify an argument of superiority one way or the other

That's hardly a valid argument, considering that RAII requires no "using"
statement whatsoever. This alone justifies an argument that there is a
difference in favour of C++ (in contrast to your assertion).

Larry's claim of "vastly superior" seems particularly baseless. Vastly?
Pure hyperbole.

Point conceded. Scratch the word "vastly".

[Peter Duniho]

Re: learn C++ or C#

On Thu, 24 Jul 2008 10:25:47 -0700, Giovanni Dicanio
<gdicanio@_nosp am_email_dot_it wrote:

"Peter Duniho"
>

>In C++, RAII provides a convenient way to deal with that, and in C#, the
>"using" statement does the same. You may prefer one syntax over the
>other, but I personally don't see a difference between the two that
>would
>justify an argument of superiority one way or the other.

>
Destructor and "scope" syntax in C++ is cleaner, simpler and more elegant
than C# bloated 'using'.

Purely subjective. That sort of claim has no place in a technical
discussion.

Moreover, there is big difference between C++ RAII and C# "using".
>
In Andre's words:
>
<quote>
Using is fine if I hold a resource in a control block, but if the
resource is held by let's say multiple lists, I have to use some kind of
smart pointers to handle the resources efficiently.
</quote>

RAII doesn't _inherently_ support "smart pointers", nor does a garbage
collecting system prevent one from implementing "smart pointers".

As I pointed out before, in a 100% GC-ed system, "smart pointers" become
unnecessary anyway. But in a mixed system (i.e. pretty much any current
platform), it's entirely possible to implement "smart pointers", and they
can work in a very similar way to that implemented with RAII.

Which only brings us back to your purely subjective complaints about
"using".

Pete

[Peter Duniho]

Re: learn C++ or C#

On Thu, 24 Jul 2008 10:35:59 -0700, Larry Smith <no_spam@_nospa m.com>
wrote:

>In C++, RAII provides a convenient way to deal with that, and in C#, the
>"using" statement does the same. You may prefer one syntax over the
>other, but I personally don't see a difference between the two that
>would
>justify an argument of superiority one way or the other

>
That's hardly a valid argument, considering that RAII requires no "using"
statement whatsoever. This alone justifies an argument that there is a
difference in favour of C++ (in contrast to your assertion).

You save a whole line of code. Wow! Yup...that definitely outweighs any
advantage that garbage collection has with respect to simplifying and
improving the robustness of memory management. After all, that's what
programmers really care about. I'd much rather save a line of code than
make it more likely that my code is correct.

>Larry's claim of "vastly superior" seems particularly baseless.
>Vastly?
>Pure hyperbole.

>
Point conceded. Scratch the word "vastly".

Replace it with "insignificantl y", and then _maybe_ you've got a point.

Personally, I think a discussion comparing/constrasting languages should
be limited to things that actually matter.

But hey, if you guys want to keep wasting time arguing about pointless
differences, be my guest.

Pete

[Larry Smith]

Re: learn C++ or C#

But hey, if you guys want to keep wasting time arguing about pointless

differences, be my guest.

http://en.wikipedia.org/wiki/Hypocrisy

[David Wilkinson]

Re: learn C++ or C#

Peter Duniho wrote:

This distinction has nothing to do with the _language_. If the OS was
entirely garbage collected, then these "non-memory resources" wouldn't
be an issue. They would be managed the same way memory is in .NET and
you'd never have to worry about disposing them.
>
Now, with certain types of objects you'd still have to deal with
closing, flushing, etc. But that's not something that RAII inherently
solves; it just happens that C++ classes can take advantage of that to
handle those operations. The OS API itself isn't based on C++ and
requires the program to deal with managing those operations.
>
In C++, RAII provides a convenient way to deal with that, and in C#, the
"using" statement does the same. You may prefer one syntax over the
other, but I personally don't see a difference between the two that
would justify an argument of superiority one way or the other. Larry's
claim of "vastly superior" seems particularly baseless. Vastly? Pure
hyperbole.

Not only is the "using" mechanism less convenient/elegant for the client of the
class than RAII (not to mention the possibility of forgetting to do it), but a
C# Dispose'd object can still be used (unlike a C++ object that goes out of
scope or is delete'd). This places an additional burden on the writer of an
IDisposable class.

IMHO, any use of a Dispose'd object should automatically cause a
"ObjectIsDeadEx ception" rather than relying on the author to test and throw an
ObjectDisposedE xception in every method.

--
David Wilkinson
Visual C++ MVP

[Peter Duniho]

Re: learn C++ or C#

On Thu, 24 Jul 2008 11:23:49 -0700, David Wilkinson
<no-reply@effisols. comwrote:

Not only is the "using" mechanism less convenient/elegant for the client
of the class than RAII (not to mention the possibility of forgetting to
do it), but a C# Dispose'd object can still be used (unlike a C++ object
that goes out of scope or is delete'd).

I was comprehending your post until "or is delete'd". There's nothing in
C++ to stop someone from trying to use an object that's been deleted, and
depending on how the memory was allocated and what the class does in its
destructor, doing so might even work for awhile.

This places an additional burden on the writer of an IDisposable class.

I don't see how it's any more burden than already exists in C++. There's
no requirement that a disposable class actually catch post-disposal uses.
It's nicer, but then so too would it be nicer for a C++ class to catch
uses that occur after destruction. And I think it's easier for a C# class
to do so, because the object is still actually allocated and the code in
the class can behave predictably; in C++, sometimes using an object after
destruction will fail immediately, and sometimes it won't.

IMHO, any use of a Dispose'd object should automatically cause a
"ObjectIsDeadEx ception" rather than relying on the author to test and
throw an ObjectDisposedE xception in every method.

I don't disagree that RAII allows for an object to simply "disappear" when
the scope is exited, but this is how "using" works in C# too. Variables
declared in the "using" statement are valid only for the scope of the
block of that statement.

And just as in C#, the reference to the variable declared in the "using"
statement could "escape" by being passed to something else, so too could a
pointer to a stack-allocated C++ object escape. RAII in C++ doesn't
actually guarantee that you can't use the object reference after the
object itself has been destroyed. It just ensures that the object is
destroyed outside a particular scope, just as "using" does.

If anything, at least with a garbage collecting system, you know that if
you have a reference to something, that's a valid reference. The object
itself might be in an unusable state, but it will always be able to tell
you that one way or the other.

Again, in terms of any practical difference between the two, any
difference is negligible and not a point worth worrying about in terms of
comparing the languages. One might save a little typing over the other
(and there are other examples going the other direction), but in the
greater scheme of things, that's just not important.

Pete

[Andre Kaufmann]

Re: learn C++ or C#

Larry Smith wrote:

>>>Multi-threading, GUI development is much easier in most of the other
>>>languages compared to the efforts you have to take in C++, because they
>>>support it out of the box. Fortunately C++ has Boost.
>>To be fair, this has nothing to do with C++ as a language (which has no
>>support for multi-threading or GUI whatsoever). You have to separate the
>>tools from the language itself.

>I don't think so. What would C++ be without the standard library ?

>
It would be another language since it must include the library by
definition. Contrast this to C# whose basic support is primitive (see the
standard for yourself). In any case, the claim that GUI development is
"easier" in C# compared to C++ has nothing to do with the languages

The RAD tools have to parse the source code, which is more complex in
C++ and therefore there aren't that much (good) RAD tools for C++ or
they feel somewhat sluggish.
So let's restrict the "easier" part on development of good RAD tools not
on using them.

themselves. It's the rich set of classes in MSFT's framework combined with
better development tools that make C# easier (noting that C# is a natural
fit for the framework unlike C++). Provide an equivalent C++ library and
better tools and it will be just as easy (not taking into account the actual
language differences).

With easier I meant the whole development experience - so it was perhaps
somewhat misleading to use the word "easier".
With development experience I mean Intellisense / refactoring / fast
compilation and so on.

There are GUI frameworks supported by different languages including C++:

C++ (/CLI): WinForms, VCL
C# : WinForms
Delphi : VCL

But IMHO the development experience in C#, Delphi is better than in C++,
just because of the compilation speed. It makes a huge difference if you
wait multiple minutes after having touched the GUI or just a few seconds.

Andre

[Andre Kaufmann]

Re: learn C++ or C#

Peter Duniho wrote:

On Thu, 24 Jul 2008 11:23:49 -0700, David Wilkinson
<no-reply@effisols. comwrote:
[...]
I don't disagree that RAII allows for an object to simply "disappear"
when the scope is exited, but this is how "using" works in C# too.
Variables declared in the "using" statement are valid only for the scope
of the block of that statement.
[...]

For scoped resource handling I think "using" is a good alternative for
RAII. But I miss RAII sometimes in C#:

E.g:

list (a) - holds a file object (f)
list (b) - holds the same file object (f)

When I remove (f) from list (a) I have to check if list (b) holds the
file object too or rely on GC to close it - but I think that wouldn't be
a good idea, since the file would be open, till the GC has disposed the
object.

In C++ I can use RAII smart pointers to ensure that the file is closed
as soon as it's not used anymore. In C# I have no automatism to handle
this.

I see that there are benefits in GC over RC = reference counting, but
IMHO both are relevant:

GC - for memory
RC - for resources


Andre