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I've read the/a pointer tutorial when i was 12, when i was 13, and just recently.
All three times, I have not figured out a use, or what it does actually
My question is, should I even bother trying to learn them? Or are they something as useless as like, the <tt> tag in html?
because, what i've learned from tutorials, they don't do anything new..
What do you mean they don't do anything new? They allow for dynamic memory allocation. They allow for pass-by-reference (since they've been around before references were), which saves you a ton of overhead when dealing with large objects. The list goes on.
Quzah.
They are one of the major things that set C/C++ apart from most other languages (mainstream one's at least). Learn them. They are useful.
useless? OMG.....they are far from being useless....Quote:
Originally Posted by s3abass
i have the same question when the first time i come to c++,
now, perhaps i got the answer :)
pointers a probably THE thing to learn in C/C++....i would say that any useful (good) program is going to have at least a couple of pointers...maybe not, but none the less, they're very very useful...
the thing is, you don't really get to see the power of pointers until you start writing more dynamic programs....watch this....this is how i grasped the concept of pointer...this is a linked list...
fun stuff......just look up linked lists...you'll *start* to see the power of pointers..Code:struct node
{
int x;
node *prev;
node *next;
};
int main()
{
node origin;
node *current;
node *temp;
current = &origin
current->x = 0;
current->prev = NULL;
current->next = NULL;
current->next = new node;
current->next->next = NULL;
current->next->prev = current;
current = current->next;
current->x = 1;
current->next = new node;
current->next->next = NULL;
current->next->prev = current;
current = current->next;
current->x = 2;
current->next = new node;
current->next->next = NULL;
current->next->prev = current;
current = current->next;
current->x = 3;
//i don't want the third node anymore, i'll just get rid of it
temp = current->prev;
current->prev->prev->next = current;
current->prev = current->prev->prev;
delete temp;
}
misplaced is a good example of a step 2 programmer.Quote:
Originally Posted by misplaced
s3abass is at step 1.
http://cboard.cprogramming.com/showt...eps#post393652
:)
woo hooo....step 2!!
...so i guess a vector doesn't use pointers? (rhetorical)Quote:
Finally, you realize that pointers don't need to be used much in C++. You use references to pass values to functions and STL containers to dynamically allocate memory. Your code is easy to read and very robust.
besides, i meant that as pointers are what sets c/c++ aside from the rest....
but i'm happy with being a step 2.
I know its rhetorical but to answer: Only the implementation knows (aside from the return types of some functions :) )Quote:
so i guess a vector doesn't use pointers? (rhetorical)
damn you black boxing!!...damn you!!
I think that pointers - raw pointers, that is - are kinda useless to C++ newbies. What for? Strings? Use std::string. PassByReference? Use references. Dynamic Memory? Use smart pointers.
The biggest advantage C++ has over C for newbies is that you don't HAVE to use pointers. Which is why I think that a good from-the-grounds-up C++ tutorial shouldn't until late.
You're a step 3 C++ programmer :) :DQuote:
Originally Posted by CornedBee
Seriously, I couldn't agree more. You should learn string, containers, references, etc. before using pointers.
What you just said is IMO what many people don't get about C++. Every C++ book for newbies I've seen has pointers and char[] quite early and containers as a late chapter or even as an appendix.
>> Every C++ book for newbies I've seen has pointers and char[] quite early and containers as a late chapter or even as an appendix.
Well, you have to learn the fundamentals to know how everything works. Once in awhile in my Comp Sci courses, I still have to create my own linked list and stuff when stl is available. You know like in calculus class you do everything by hand but then in practical, real life, you use a tool to generate the solution for you
There is a difference between teaching somebody how something works and teaching them to do it the hard way. Too often C++ classes and books teach people to code the "wrong" way. In my opinion, it is far more beneficial to teach more appropriate techniques first, then go into finer detail on why those techniques work. This is why I would expect someone to learn C++ before assembly.
Too often I see newbies (including myself at one point) who are confused with pointers and low level techniques and have a hard time getting anything done, and then struggle to break the habits they picked up once they move on to more "advanced" topics.
i personally like using pointers...well, knowing how to use them...of course it's a lot easier to work with the stl, but i'm certainly glad that i learned how to use them first. i believe i have a lot better understanding of my programs from know how the memory is set up and what not...
>> In my opinion, it is far more beneficial to teach more appropriate techniques first, then go into finer detail on why those techniques work.
I just thought that pointers are not one of those finer details. I perceived that basic c++ include pointers. You have to know them just like you know int, float, etc; then build up from there.
I would say that one examples of finer details are instructions involved in calling new (alloc, and all that stuff I'm not knowledgeable yet).
See, I understand if people like pointers, but I just think that it's a very bad idea to push them to newbies. You can read up more on my thoughts in the introduction to my tutorial.
http://stud3.tuwien.ac.at/~e0226430/...ationale.xhtml
Not IE-compatible.
What if I say that
if you a Comp Sci student then you have to know pointer early. If a book is designed for Comp Sci course it has to mention pointers; if it is one of "C++ for Dummies" or "Teach Yourself C++ in 21 Days", you decide.
I would certainly dislike the idea if pointers are not taught in one of the 100-level (first year) courses in Comp Sci.
Many people are now learning Java as a first language in intro level CS courses. Are they worse off because they aren't learning pointers first? I personally don't think so.
Pointers, while important in general, are not necessary for beginners who code in the C++ style. I would say that newbies should not even need to use new until at least the second half of their intro course. Why does someone new to programming need to know about dynamic memory allocation? Program structure and flow, loops, if statements, functions and variables are all more suitable for introductory topics.
The strings, arrays, and other stuff is general used without being explained because otherwise the student wouldn't be able to see the results of their code. Whether you use C++ style or C style you still want to minimize the time it takes to teach these peripheral details in order to focus on the more important basic topics. Later on, when it is time to discuss the slightly more advanced language features, you can choose how much detail you want to go into. I just think that these topics should be made as simple as possible in the beginning for newbies so they can concentrate on the really basic stuff.
>> Many people are now learning Java as a first language in intro level CS courses.
I thought they're switching to Java 'cause they don't want to use pointers at all?
I need clarification on this one. If Java is taught first, doesn't it become the main language in the school? The whole subsequent material will then be implemented with Java? (Unless you take Intro to Fortran and the like)
The first "programming" class I took at college was Pascal. Now that its gone people take an algorithm design course or VB first. I wouldn't say either of these are the main language courses. Heck C++ is the 3rd one I've taken here and all the upper classes are implemented with C++.
I honestly don't know what they are teaching in college now. I had just heard that many universities and high schools were switching to Java as their main programming language. My experience was almost exactly like Thantos (right near Sac, too), Pascal, then C, then C++ and C++ for all upper division stuff. We even had to learn C++ on our own after the C class, and were expected to use C++ two weeks into a data structures class.
If the point of taking Java is to avoid pointers completely, then that backs up my point of avoiding low level constructs when teaching somebody programming for the first time. Even if a student knows how to program and is just learning C++, better coding style should be taught in the beginning. That's just my opinion, but I know it is shared by many others.
Our University switched to Java for the first programming course I think 3 or 4 years ago. Since then, most other courses use Java, too. One lets us choose between C++, Java and C#. One that discusses generics used C++, I think, until last semester, but now uses Java5. And so on.
So, in general, if Java is the first language you learn, most subsequent stuff is done in Java, too.
Is it really so tough to teach someone about pointers and their proper use? I understand that many people are confused by pointers but I think the reason why is because of the black box approach. I read alot about assembly and computer architecture and low level addressing modes and when it came to pointers I understood how they worked. Maybe it is just because they don't provide enough detail or enough context. Whenever I read a C or C++ book they very rarely go into to much detail about memory architecture and addressing modes. I think they should teach basic assembly or an introduction to the instruction set before they teach a high level language. Nothing too advanced. IMO more knowledge is better.
What is that quote?
Quote:
"A little learning is a dangerous thing; drink deep, or taste not the Pierian* spring: there shallow draughts intoxicate the brain, and drinking largely sobers us again."
-Alexander Pope (1688-1744), _An_Essay_on_Criticism_.
I agree that this information should be taught. It is essential to the understanding of good C++ techniques.Quote:
Originally Posted by manofsteel972
To me it boils down to teaching the student the best way to do something first. I highly doubt someone new to programming really understands what is going on when they use a character array to hold a string. They are only trying to understand the syntax. So if they aren't going to understand the inner workings of what they are using, why not teach them the easier syntax that also happens to be more flexible and robust. Only later, when they are focusing on how these things work, should they be exposed to the details that were glossed over in the beginning.
In my opinion, too many programmers who think they know C++ really only use C with classes because they were taught the C way of doing things first. I doubt that those people understand pointers any better than those who were taught C++ style from the beginning. So no, it isn't so tough to do it, but it is better to wait a little longer than most courses do now.
I agree that these things should be taught, but I think they should be taught after the basics. My reasons for this are threefold:
1) People who learn on their own want to DO stuff. The best way for them to learn is a way where they have results. People who have to learn still prefer it that way, but they won't walk away if it's different.
2) C++ is a high-level language. If you want to use it effectively, you need to think in design patterns first, how to best map your program design to a code design. Then you can think of how to map the code design to actual code. Learning pointers and this stuff teaches the latter part first, and I think that's a mistake.
3) Building on 2, programmers, especially hobby programmers, often get caught up in the details. They worry too much about minor stuff and don't get anything done. Again, by teaching the high-level techniques first, you can get them to think big in the first place.
I understand your point of view. I guess in my mind, I am able to grasp the concepts better because I can visualize the inner workings. I can see how a character array would be represented in memory. I can see they are a series of 1 byte chunks and that that they are stored in a linear memory area that begins at some address. that address being the pointer. I can see that bye adding 1 byte or 2 bytes or 3 bytes I can access the 1st second or 3rd char variable. in the string. I can see that it has a specific size and that if i index past the end I will end up in some other memory space. Everyone has different learning styles I guess this is just mine. To me having something to anchor my knowledge to is less discomforting then floating on the knowledge of it works somehow but all I need to to do is put this symbol before it to make it a pointer and then put this other symbol before it to make it a reference. Granted it is all a time constraint. What makes for efficient learning? How can I cram the most knowledge into my head in the least amount of time and have it stick? I guess I am stuck in the scientific mode of how does it work so I can understand how everything else works.
I'm extremly glad i'm learning C first. I've found that an indepth understand of how C works, is great to understand other languages, scripting and otherwise. C++ is no exception - regardless of of the extra libraries and data structures B.S. used to make it "simplier".Quote:
The fact is, C++ is far easier to learn than C. And I'm going to take advantage of that in this tutorial. All I expect of you is to accept that you're using things without knowing how or why they work. Explanations will come in time.
Serioulsy if your studying computer science shouldn't you study computer Science. I'd love to see some of those first year students have a look at the JVM and the ubelievable usage of pointers its said to make use of.Quote:
Many people are now learning Java as a first language in intro level CS courses. Are they worse off because they aren't learning pointers first? I personally don't think so.
Java is a lanuguage built atop C and C++. It is the product of someone's imagination in an attempt to facilitate programming and be the the new PL-1. As it result its failed miserably(regardless of how much shelf space it takes up). Have you looked at JAVA 5?
The point is C (and more importantly the understanding of pointers in C) gives you unbelievable power and advantage when coding. Sure if you want to use a language that abstracts all of that for you, fine, But then why bother going into computer science at all. In fact forget java and learn HTML.
:rolleyes:
Java is good for what it is, a dumbdowned version for RAD. Serioulsy ppl need to stop comparing it to C there is none.
ditto. even if i am a hobbyist programmer ;)Quote:
What makes for efficient learning? How can I cram the most knowledge into my head in the least amount of time and have it stick? I guess I am stuck in the scientific mode of how does it work so I can understand how everything else works
Of course pointers and other low-level stuff should be taught. Of course it helps you understand what is going on. Of course computer science is more than just learning the syntax of a language.
The argument is that when teaching C++ specifically, the low-level information should be not used to explain what to do in your program, but instead should be used to explain how your program works.
Are you trying to troll with the HTML comment? Collect all programming languages (and no, HTML isn't one) and you'll see that abstraction in all of them forms a smooth spectrum, with assembly on one end and functional languages on the other. Each goal has an optimal abstraction level (if it's small enough, if it's larger you need to break it down to subgoals) and you'd best use the language that is closest to this abstraction level. Obviously you're not going to implement a JVM in Java.
But you're using libraries in C, are you not? You're using the stdio library, because it does complex and OS-specific tasks such as writing data to the console for you. Think of the JVM as that: a library. A big library, written in C(++?), only that you write the code with a slightly different syntax.
To what effect? The people who wrote the JVM had years of programming experience. What could any first-year CS student do with their code?Quote:
I'd love to see some of those first year students have a look at the JVM and the ubelievable usage of pointers its said to make use of.
I have. What's your point?Quote:
Have you looked at JAVA 5?
Java is good for what it is, which is not what you say it is. So is every language, or nearly so. Languages are written with a purpose, and since there are many purposes there are many languages that fit the purpose.Quote:
Java is good for what it is, a dumbdowned version for RAD.
How did we end up talking about Java anyway? We were talking about different aspects of C++.
No, it's used to make it more abstract. Believe it or not, there's a difference.Quote:
C++ is no exception - regardless of of the extra libraries and data structures B.S. used to make it "simplier".
In C, there are no alternatives to learning pointers in the beginning. When learning C, you should learn pointers as fast as possible.Quote:
Originally Posted by caroundw5h
That is the reason pointers are generally taught so early in C++. C++ books begin by teaching the whole C language (replacing printf with cout) and then moving on to C++-specific stuff.
Note that I'm not saying that pointers are hard to learn or anything. They are extremly simple, you just have to get the syntactic weirdness for declaring, dereferencing and taking the address of an object.
It just better to learn to use STL before learning pointers.
When you make statements like this, I'm beginning to doubt you know C++ that well.Quote:
Originally Posted by caroundw5h
You are using pointers much more in Java than in both C and C++. References in Java are equivalent to pointers, except that you cannot use pointer arithmetics like + and -.Quote:
I'd love to see some of those first year students have a look at the JVM and the ubelievable usage of pointers its said to make use of.
To say Java is simpler because it lacks pointers is plain wrong. Java is simpler for other reasons, but if you don't understand pointers, you should try C++ instead.
pointers are important and only when u get involved in programming with different approaches for the same problem you will come to know of the difference between the approaches.....
all the guys out there...i suppose i am right.........
do we have *two* discussions/arguments about pointers and references? check the other one...and u'll see that people think it's funny that we have two posts on pointers going on....