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I'm thoroughly intrigued by Scheme, and have started with some toy programming examples, and am reading through Paul Graham's On Lisp.
One thing I haven't been able to find is a book or website intended to teach Scheme to "OO people", i.e. people like myself who've done 99 % of their coding in c++/Java/Python.
I see that closures are sort of object-y, in the sense that they have local state, and offer one or more functions that have access to that state. But I don't want to learn Scheme only to port my existing habits on to it. This is why I'm learning Scheme rather than Common Lisp at the moment; I fear that CLOS might just serve as a crutch to my existing OO habits.
What would be ideal is a book or website that offers case studies of problems solved in both an OO language, and also in Scheme in a Schemey way. I suppose I would most appreciate scientific computing and/or computer graphics problems, but anything would do.
Any pedagogical leads would be much appreciated.
I doubt CLOS would serve as a crutch for old habits, I found it to be pretty different from the OO style in C++/Java/Python, and very interesting. I don't understand all the details, but I would recommend Peter Seibel's Practical Common Lisp. If you are reading On Lisp without much trouble, you should be able to dive into the chapters introducing CLOS in PCL. Also, I'd recommend his Google Tech Talk comparing Java and Common Lisp.
Here's a few more recommendations to make this a more full-fledged answer:
The classic text Structure and Interpretation of Computer Programs covers quite a few examples in chapter 3 of building modular systems using closures (and addresses issues with introducing state and mutability). Chapter 2 includes some generic and data/type-directed programming which could be helpful for motivating study of CLOS. This book really needs no introduction though, it's a towering work, and I've only been reading it slowly since the spring. Highly recommended if you are interested in Scheme.
While SICP is a great book, it's not without its flaws: A really interesting look at these is the essay "The Structure and Interpretation of the Computer Science Curriculum" which elaborates on a few criticism of SICP, and is written by the authors of How to Design Programs (I haven't read HTDP but I hear it's very good). While this essay won't teach you specifically what you are looking for - comparing functional and OO programming - it is really interesting anyway. Their freshman undergraduate course starts with a first semester introduction to functional programming using Scheme (I think, PLT/Racket) and is followed by a semester of OO programming with C++ or Java... at least that's the course they describe in the essay.
These slides from Peter Norvig address some of the design patterns common in OO programming and show why they are missing or unnecessary in dynamic, functional languages like Scheme and Lisp: http://norvig.com/design-patterns/
I cautiously recommend the book by the same authors as the Little Schemer books: A Little Java, A Few Patterns. I can't say for sure if this is a really a good book or not, it was incredibly strange and there are some really bad typesetting decisions (italic, serif, variable-width, superscript doesn't belong in a text on programming), but it might be interesting to take a look at. You can probably find it cheap, anyway. Don't take this recommendation that seriously. I think it would be better to stick to the Scheme texts.
p.s. I have to disagree with one comment stating that functional programming is not as complicated at OO programming, I think that's grossly misstating it. Functional programming in all its breadth is truly mind-boggling. When you go beyond map/filter/reduce and first-class functions, and take a look at other things in the functional realm like lazy evaluation, avoiding side effects and mutation, and the strong, static-typed languages, it gets pretty interesting, and is certainly just as complicated as traditional OO programming. I've only just scratched the surface myself but have discovered a great deal of new ideas. Programming is complicated business, whether OO or functional.
Congrat you, my friend ! Love cs, love functional programming.
If you are python developer it takes 3-4 days to think in scheme
Here is the best simple tutorial I have ever met http://www.shido.info/lisp/idx_scm_e.html
I found this course http://cs.gettysburg.edu/~tneller/cs341/scheme-intro/index.html and it may be useful for you
One beginner's resource that is very helpful and geared very much toward the casual reader is "The Adventures of a Pythonista in Schemeland". It's written (obviously) from the point of view of a Python programmer taking first steps with Scheme. One especially nice thing about it is that it includes an overview of the current implementations and compatibility issues between each scheme implementation, which, unfortunately, can cause some headaches when you're just starting out.
With regards to object systems, these two documents (linked from here) give nice examples of very simple toy implementations using closures that I found helpful in understanding their use in capturing state.
If you are starting off with Scheme, have a look at How to Design Programs. This book presents the "Schemey" approach to problem solving. I don't think there is a book that compares OO and functional solutions to the same programming problems. But there is a nice presentation that shows how dynamic languages like Scheme could provide simple solutions to problems that demand complex design patterns in statically typed OOP languages.
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Closed 10 years ago.
I have been programming in object-oriented languages for years now but secretly I look at some of the things my colleagues do with envy. A lot of them seem to have some inner OO instinct that I don't have - no matter how hard I try. I've read all the good books on OO but still can't seem to crack it. I feel like the guy who gave 110% to be a professional footballer but just didn't have the natural talent to make it. I'm at a loss and thinking of switching careers - what should do I?
I would say focus less on the OO programming and focus more on the OO design. Grab a paper and a pencil (or maybe a UML modelling tool), and get away from the screen.
By practicing how to design a system, you'll start to get a natural feel for object relationships. Code is just a by-product of design. Draw diagrams and model your application in a purely non-code form. What are the relationships? How do your models interact? Don't even think about the code.
Once you've spent time designing... then translate it to code. You'll be surprised at just how quickly the code can be written from a good OO design.
After a lot of design practice, you'll start seeing common areas that can be modularized or abstracted out, and you'll see an improvement in both your designs and your code.
The easiest way is to learn concepts such as SOLID, DRY, FIT, DDD, TDD, MVC, etc. As you look up these acronyms it will lead you down many other rabbit holes and once you are done with your reading you should have a good understanding of what better object-oriented programming is!
SOLID podcasts: http://www.hanselminutes.com/default.aspx?showID=168, http://www.hanselminutes.com/default.aspx?showID=163
SOLID breakdown: http://butunclebob.com/ArticleS.UncleBob.PrinciplesOfOod
DRY: http://en.wikipedia.org/wiki/Don%27t_repeat_yourself
FIT: http://www.netwellness.org/question.cfm/38221.htm
DDD: http://dddcommunity.org/
DDD required reading: http://www.infoq.com/minibooks/domain-driven-design-quickly
TDD: http://en.wikipedia.org/wiki/Test-driven_development
MVC: http://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller
And yes, rolling up your sleeves and coding is always a good idea. Make a small project to the best of your current abilities. Then read an article from above. Then refactor your code to meet the needs of what you just read. Repeat until you have refactored the hell out of your code. At the end you should not only know what OO is all about but you should be able to explain why it is important and how to get their the first time. Learning how to refactor is a key to good code too. What is right now is not right tomorrow.
Too many people think of coding first, objects, last.
You can read all the books you want but that's not going to teach you how to think in an object-oriented fashion--that takes practice and a certain methodology.
Here are a few methods that have
helped me: When you're away from
work and open-minded you can
practice by looking at everything as an object. Don't look at these
objects and wonder how you're going
to program them, look at them as
properties and functions only and
how they relate or inherit from each
other. For example, when you see a
person, they are an object and
therefore would represent a class.
They have properties like hair
color, skin tone, height, etc. They
do certain functions as well. They
walk, talk, sleep, etc. Some of the
functions these people do returns
results. For example, their working
function returns a dollar amount.
You can do this with everything you
see because everything is an object.
Bicycle, car, star, etc.
Before coding a project, design it by
using post-it notes and a dry-erase
board. This will make good practice
until you get the hang of this.
Think of your specific
object/function/property. Each of
those items will have its own
post-it note. Place them as a
hierarchy on the dry-erase board. In
this regard, function/properties
will be placed under the object. If
you have another object, do the same
for that one. Then ask yourself, do
any of these post it notes
(objects/functions/properties)
relate to each other. If two objects
use the same function, create a
parent object (post-it note) and put
it above the others with the
reusable function under the new
note. Draw a line using the
dry-erase marker from the two child
objects to the parent.
When all this is done, then worry
about the internals of how the class
works.
My suggestion would be to learn something different.
Learn functional programming, and apply what you learn from that to OOP. If you know C++, play around with generic programming.
Learn non-object-oriented languages.
Not just because you should use all these things as well (you should), or because they should completely replace OOP (they probably shouldn't), but because you can apply lessons from these to OOP as well.
The secret to OOP is that it doesn't always make sense to use it. Not everything is a class. Not every relationship or piece of behavior should be modeled as a class.
Blindly trying to apply OOP, or striving to write the best OOP code possible tends to lead to huge overengineered messes with far too many levels of abstraction and indirection and very little flexibility.
Don't try to write good OOP code. Try to write good code. And use OOP when it contributes to that goal.
In many fields there's a "eureka" moment where everything kind of comes together.
I remember feeling frustrated in high school geometry. I didn't know which theorem to apply on each step of the proof. But I kept at it. I learned each theorem in detail, and studied how they were applied in different example proofs. As I understood not only the definition of each theorem, but how to use it, I built up a "toolbox" of familiar techniques that I could pull out as needed.
I think it's the same in programming. That's why algorithms, data structures, and design patterns are studied and analyzed. It's not enough to read a book and get the abstract definition of a technique. You have to see it in action too.
So try reading more code, in addition to practicing writing it yourself. That's one beauty of open source, you can download lots of code to study. Not all of that code is good, but studying bad code can be just as educational as studying good code.
Learn a different language! Most developers using only Java (just as an example) have only a limited understanding of OO because they cannot separate language features and concepts. If you don't know it yet, have a look at python. If you know python, learn Ruby. Or choose one of the functional languages.
The aswer is in your question ;)
Practice, practice, practice.
Review your own code and learn from the mistakes.
TDD has helped me most in improving my overall skillset including OOP.
The more code you write, the more you will notice the pitfalls of certain programming practices. After enough time, and enough code, you will be able to identify the warning signs of these pitfalls and be able to avoid them. Sometimes when I write code, I will get this itch in the back of my mind telling me that there may be a better way to do this, even though it does what I need it to. One of my greatest programming weaknesses is "over-analyzing" things so much that it starts to dramatically slow down development time. I am trying to prevent these "itches" by spending a little more time on design, which usually results in a lot less time writing code.
...secretly I look at some of the things my colleagues do with envy. A lot of them seem to have some inner OO instinct that I don't have - no matter how hard I try...
I think you have answered your own question here. Reading good code is a good start, and understanding good code is even better, but understanding the steps to get to that good code is the best. When you see some code that you are envious of, perhaps you could ask the author how he/she arrived at that solution. This is entirely dependent on your work environment as well as the relationships with your colleagues. In any event, if anyone asks me the thought process behind any code I write, I don't hesitate to tell them because I know I would want them to do the same for me.
Language designers have interpreted "Object Oriented Programming" in different ways. For instance, see how Alan Kay, the man who first used the term OOP, defined it:
OOP to me means only messaging, local
retention and protection and hiding of
state-process, and extreme
late-binding of all things. It can be
done in Smalltalk and in LISP. There
are possibly other systems in which
this is possible, but I'm not aware of
them.
(Quoted from http://userpage.fu-berlin.de/~ram/pub/pub_jf47ht81Ht/doc_kay_oop_en).
It might seem strange that he don't consider Java and C++ OOP languages! But as the designer of one of the first and best OOP languages (Smalltalk) he has his own valid reasons for that. Why did Alan Kay consider Lisp an Object Oriented language but not Java? That question demands serious consideration by anyone who claims to understand OOP.
Erlang has an altogether different implemntation of OOP, Scheme has another.
It is worth considering all these alternative views. If possible learn all these languages! That will give you a broader outlook, put some new and powerful tools in your hand and make you a better programmer.
I have summarized my experiments with implementing an OOP language, based on ideas borrowed from Smalltalk, Scheme and Erlang in this article.
public void MasteryOfOOP()
{
while(true)
/* My suggestion is: */
DO: find a lot of well-written object oriented code and read it. Then
try to use the insights from it on your own coding. Then do it again. Then
have a colleague who is a good OOP look at it and comment. Maybe post a chunk
of your code on SO and ask for how it could be improved.
Then read some more of those books. Maybe they make a little more
sense now...?
Now go back to the top of this post, and do it again.
Repeat Forever.
}
}
If you're lost as to how to design object-oriented systems, start with the data. Figure out what stuff you need to keep track of and what information naturally goes together (for example, all of the specs of a model of car group together nicely).
Each of these kinds of thing you decide to track becomes a class.
Then when you need to be able to execute particular actions (for example, marking a model of car as decommissioned) or ask particular questions (for example, asking how many of a given model of car were sold in a given year), you load that functionality onto the class it interacts with most heavily.
In general, there should always be a pretty natural place for a given bit of code to live in your class structure. If there isn't, that signals that there's a place where the structure needs to be built out.
There's too much information about objects. The most important thing is to master the basics and everything falls into place more easily.
Here's a way to think about objects. Think about data structures in procedural languages. They are a group of fields without behaviour. Think about functions that receive pointers to those data structures and manipulate the latter. Now, instead of having them separate, define the functions inside the definition of the the structures and assume the functions usually receive a pointer to the data structure to manipulate. That pointer is called this. In sum, think about objects as the combination of status (data) and behaviour (methods - the fancy name for functions in OOP).
This is the absolute basic. There are three more concepts you must absolutely master:
Inheritance - This is all about code reuse.
Encapsulation - This is all about hiding the implementation from the interface. Simply put, everything ought to be private until proven otherwise.
Polymorphism - It doesn't matter the type of the reference variable, but the type of the actual instance to know which behaviour (method) is called. Java doesn't make it easy to have this concept very visible because by definition everything is polymorphic. .Net makes it easier to understand as you decide what is polymorphic and what is not, hence noticing the difference in behaviour. This is achieved by the combination of virtual and override.
If these concepts are very well understood, you'll be fine.
One last final tip: You mention the best books. Have you read "Thinking in Java" by Bruce Eckel? I recommend this book even to people who are beginning in .Net, as the OOP concepts are clearly laid out.
Become more agile, learn junit testing and study about Domain Driven Design. I suggest the book Domain-Driven Design: Tackling Complexity in the Heart of Software although it's a bit tough at some points.
OOP skills comes over time. Reading 1, 2 ...10 books doesn't cut it. Practice writing some code. If you are working in a programming enviornment...that can be helpful. If not try getting into one. Offer to develop some application(s) for free. You have to get your hands dirty. Remember...no application is perfect from the ground up.That's why there is re-factoring.
Also...don't get carried away with the OOP too much...it somes over time. Worry about developing fully functional applications.
Try some programming in Self, one of the most pure OO languages around. So pure, in fact, that it doesn't even have classes, only objects. It also doesn't have variables, fields, statics, attributes, only methods. Also interesting is the fact that every object in the system is also an object on the screen and vice-versa.
Some of the interesting papers on Self are Prototype-Based Application Construction Using SELF 4.0 (the Self tutorial), Self: The Power of Simplicity and Organizing Programs Without Classes. Also, Self: The Video (Randall B. Smith; Dave Ungar) is terrific, having two of the language's designers explain Self's ideas.
This works for pretty much any concept, actually, at least for me: find the language which most purely embodies the concept you want to learn about and just use it.
OO finally clicked for me after I tried to program a bank-like program that handled transactions, calculated interest, and kept track of it all. I did it while I was learning Java. I would suggest just trying it, completing it, and then when you're done go look at a GOOD solution and see what you could've done better.
I also think OOP skills strenghten mostly with practice. Consider changing your company, if you've been there for more than 3 years. Certainly, this is not valid for all jobs, but often a man gets used to the projects and practices at a company and stops advancing as time passes.
Roll up your sleeves and code!
You said the answer yourself: practice. Best solution for this is to develop a game. Use the concepts you learnt in the books there.
Have you read the chapter on OO from the first edition of Scott Meyers "Effective C++" book? It didn't make it to later editions, but it was a great explanation. The title was basically "say what you mean, mean what you say" about suitable conventions.
Actually, you might like to see my answer to a similar question over here.
HTH
cheers,
OOP is not a thing you can master by reading thousands of books. Rather you have to feel the inner concepts. Read anything but try to feel what you read. Build a concept in the back of your mind and try to match those concepts when you face a new scenario. Verify and Update your concepts as you explore new things.
Good luck!
Plan things out. Ask yourself how you want your objects to relate to eachother and seek out how things can be changed and modularized.
Code things in such a way that if you wanted to change 1 piece of the code, you only have to change that 1 piece of code and not 50 instances of it.
beer helps. seriously. lie out on a couch with an A3 sized scribble pad, a pen and a beer. Lock the dog, cat and wife outside. And think about the problem while relaxed. Don't even dare draw an API on it!
Flowcharts, Responsibity cards (CRC) and beer (but not too much) go a long way.
Easiest way to refactor code is to not have to in the first place.
http://misko.hevery.com/code-reviewers-guide/
Those small simple rules will make you a better OO programmer. Follow the rules religiously as you code and you will find your code is better than it would otherwise be.
You'll also want to learn the Solid Principles: http://butunclebob.com/ArticleS.UncleBob.PrinciplesOfOod
As much as these principles and ways of programming cause debate, they are the only way to truly write excellent code.
You may already write code this way and not know it-- if so, great. But if you need a goal to strive towards, these are the gold standard.
Give up! Why do you need that that OOP? Just write some usable app. Doesnt metter using OOP, procedual or functional approach.
Whataver approach you choose Python language should be sutable to practice it.
You're my target audience. Look at Building Skills in OO Design
Perhaps this can help.
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Closed 9 years ago.
I am learning programming. I plan on learning C and Objective-C this summer. I bought the C for Dummies book but it is a complete waste of time. It's way too many pages! Are there any good books I should read? Or should I just learn C from websites? What would be the fastest way because I really want to learn it fast and start learning Objective-C too.
Thank you
Also, how long does it take to learn C? Until I move to Objective-C 2.0
There's no need to rush. Learn at your own pace and find your optimal way of learning.
If reading is your thing, then try to read some books and take it slowly.
If you find a concept you grasp, practice. If you find a concept that you don't quite get, experiment. Once you think you understand the concept, try re-reading the material to see if you understand it the second time.
I found out that I wasn't really good at learning though books -- I generally had to get the first kick-start with a structured lessons in a classroom. A semester course at a community college on Java was able to nudge in the direction of being able to begin effectively learning on my own. See if there are any programming courses offered in your school.
(Although at your age it may be a little bit difficult to find -- I didn't get any formal classes until community college -- my high school did not offer any programming courses.)
One of the things to be careful of is learning it the wrong way.
Rushing through material, or reading poorly written, inaccurate learning material can lead to a situation where you'll need to "un-learn" the concepts and re-learn it the right way.
In that respect, the K&R book (The C Programming Language by Kernighan and Ritchie) would be the "right way" of learning, but it's not a very approachable book. That isn't to say that it is the definitive book on C -- but even after programming in C for a couple years, I still try to take read it a bite-size at a time.
But then again, I can't really think of other "great" sources for learning C. My recommendation would be to take a look at K&R and work on a few pages at a time. Don't think about reading it like a regular book -- read one section, try it out. Do it little-by-little. Once again, don't rush. Work at your own speed.
And be sure to write code. Without seeing it working, it's going to be difficult to learn programming. And don't have huge expectations at first, as most of learning C at the beginning will involve programs that deal with only text.
Once you get a handle of things, try to write clean code that is readable by others -- that should be a motivation to write clean and clear code, and it will force you to think harder about what you're doing.
It's going to be a long adventure, so take it a step at a time. Good luck!
For learning C, I highly recommend Learn C on the Mac, by Dave Mark. Not only is it aimed at beginners, but it also teaches you a lot about the important fundamentals of programming and computer science (e.g. data structures, recursion, etc.). It's very accessible, well-written, and easy to read. Plus, I found the examples engaging and interesting to work with. After that, if you really want to solidify your foundations in C, I'd recommend trying to moving on to The C Programming Language. It's a challenging book, so take it slowly. If you find yourself having too much trouble with it, I'd say you can just skip to Objective-C, and then come back to The C Programming Language later, once you've gained more familiarity with programming in general.
A lot of people will probably recommend The C Programming Language (a.k.a. "K&R") as your first book to read on C. No doubt it is a very well-written C book (and it's short too—only around 200 pages), but I'd say it'd be a little intimidating as a 12-year-old's first exposure to C: it's pretty dense and hardcore. You can tell that it's definitely aimed at an older audience with a strong background in computers/engineering. But nevertheless, if you already know the basics of programming, reading K&R will give you invaluable insight and understanding of C. You should definitely read it at some point in your programming endeavors.
Anyways, for Objective-C, if there's only one book I could recommend, it would most definitely be Cocoa Programming for Mac OS X, by Aaron Hillegass. It's really not that long (~400 pages or so, although I'd reckon that a lot of that is due to the number of illustrations in the book), and you can get some pretty cool projects up and running in an afternoon. It's very clear and easy to read, the examples are practical and interesting to follow, but most importantly, it's got this right blend of not being too intimidating while still managing to provide you with solid information. Plus, it'll teach you more than just Objective-C: I found that I had learned some very useful design patterns, for example, by learning how some of the components of Cocoa worked.
When I look at the title of this question, I am guessing you are 12.
I started programming when I was 13 (I am now 14).
I found that learning depends on what kind of a learner you are!
I hate reading, I have the attention span of a moth and I learn best from videos. Therefor, I am a "visual learner". Try to find out what kind of "learner" you are, then do it that way. Remember, the easiest way is the fastest.
PS, here is a little tip. It may be frustrating (aseptically at our age). If you get frustrated, just put it down for like 10 minutes. Then come back and do research on what your learning. Programming WILL get very frustrating at times.
EDIT:
By the way, I like to learn through video :p
Stanford University posts online the lectures, class notes, and assignments for CS193P (an iPhone development class). If you don't know C or Objective-C at all, it might be tough, but I highly recommend this if you intend to do iPhone development.
I think I've read every Cocoa and Objective-C book out there, and most enjoyed Aaron Hillegass' Cocoa Programming for Mac OS X.
I would take a look at The C Programming Language (K&R C). It's much less than 1000 pages and I think you'll find it well worth your while. As htw said, books do serve a purpose in that they provide a thorough and structured approach. K&R C in particular will give you real insight directly from the creators of C.
That's not to say you shouldn't Google things, read open source code, write little practice programs, etc. It all helps. Just remember to be patient. There's a lot out there.
Checkout out http://www.cprogramming.com/ or and online K&R type book
Don't be impatient; take your time. Follow tutorials, dissect short snippets of code, you'll get the hang of the language. Most importantly, write code yourself and learn from your bugs/errors.And follow Stack Overflow ;)
I've been where you are. It wasn't fun. This is what saved me:
(Apparently new users aren't allowed to post hyperlinks, so google for "steve summit C", use either the first or the third link, and then click "introductory C programming class notes")
It's a C class by a guy named Steve Summit. Super easy to follow, much easier than K&R, imo.
Also, it's free, and there aren't any ads. I loved it. It's how I learned C. I hope it'll do the same for you.
There is nothing so educational as a piece of code you can run and tweak. Code examples in books can be really bland and not very applicable. The exception to this rule was the Perl Cookbook which is jammed packed with really useful little snippets for your perl programs.
The topics (or 'idioms') in it were so useful and so applicable across languages that some smart folks have taken to replicating them in different languages. Each has a varied level of completeness, but it's interesting to see how different languages do the same things.
Take a look here http://pleac.sourceforge.net/ for nuggets of programming wisdom that you can shake a stick at. At the very least its interesting to see how simple things written in one language require reams of code in another.
Were I starting to learn programming again I would probably pick something easy and forgiving, a dynamic language, like Python, Ruby etc. Once you get your head around the basics in one of these (flow control, data structures etc) it will make learning C/Objective-C so much easier. Also you'll find that you'll want to write once-off tools and scripts to help you in your Objective-C development that would be tedious and time consuming to write in C but are a matter of lines in a modern dynamic language. Never hurts to have another tool in your belt.
Good luck
Honestly, I learned Java as my first programming language (I discovered it in high school and decided programming was fun and it was what i wanted to do)
I just now picked up Obj-C in a few weeks, reading a little bit from some books, but not a whole book, and using the internet a lot if i can't figure out the syntax (format/grammar of how the program should be structured and written) for something etc.
How fast you can pick up a language depends on how much you understand the fundamentals of programming. You will only get better at it with time and practice.
If you can understand the fundamentals of programming in general then you should be able to apply it to any language, the hard part is learning and remembering the syntax of different languages. Like in Java, you don't have to do memory allocations, but in C, C++ and Obj-C you do. I've never written a C or C++ program, but now that I've learned and written some programs in Obj-C (i've been making iPhone stuff, it is fun) I'm sure I could pick up C and C++ like it's nothing.
You don't have to learn C first in order to learn Obj-C is what i'm trying to say. But it never hurts to know multiple languages.
It is all about your level of understanding how a program works, how to structure one. I love objective-C because it is Object Oriented like Java so it was easier for me to understand and learn quickly, just had to get used to some of the differences in syntax
(I'm also getting close to graduating from college now so I'm surrounded by programming stuff, from procedural languages like ada to object oriented like java, and knowing the nitty gritty behind the scenes stuff that makes a program work, so understanding and learning a new language has gotten a lot easier for me, you start seeing how they relate and don't relate and it is cool)
It is great that you are starting so young. I'm sure you'll pick up on this stuff real fast, and if it is something you really enjoy, it will be even easier.
Good Luck! and have fun! programming can be so frustrating... like, spending 3 hours debugging when you find out it was because you if statement used a grater than instead of grater than or equal too or something like that. but, once you are done with the program, it is so rewarding, and then you just want to make it better and better haha.
I dunno if this helped at all, I hope it did, somehow...
=)
the way i learned quickest was to watch short video tutorials.
If you really want to start with C, I would start by just reading the first three or so chapters of C for Dummies, just to get a feel for how the language works. After that, I recommend going through web tutorials. Good web tutorials will have short code that explain specific functions, and the like.
As a 13-year old, though, I recommend starting with PHP. It's a simpler language to learn than C, but it's based off of C, so it won't be hard to make the transition, whenever you do so.
Different people have different preferred ways of learning. You can see that in the variety of responses above.
So how do you like to learn? Do you like to sit by yourself with a book and a computer? Do you like to sit in a classroom and absorb learning? Do you prefer set exercises, or mini-projects?
When I learn new programming languages, I find it helps me if I have a small application or problem to work on. I prefer to have a problem to work on. If you have a little project of your own that you always wanted to do, use that. If not, as someone above suggested, join a robotics group. Set up a web page and write some programs to do stuff for that.
Look on the web for programming challenges. Google has a fun one every year.
If you want an idea, write a sukoku checking program. Then later, write a sudoku solver!
I like to use a variety of books, rather than just sticking to one or two of the ones suggested above. Find a book whose style you like. Try a few from the library until you find one or two that really click for you.
Personally, I like O'Reilly Publishing books for their chatty and readable style. I learnt C from Deitel, which is more of a classroom style textbook, but it has lots of examples and discussion points.
As you work through examples on your computer, you might wonder how things change if you tweak the code. I learn a lot by first running the example code suggested in a text, but then changing it to see what happens. If I get what I expect, it's a sign that my understanding is pretty good. If I get something unexpected, I try to figure out how I misunderstood what I did.
One last suggestion. Why not start with Python rather than C? I hear that a lot of schools are teaching Python to their kids. The reasons I suggest this are:
Python is pretty easy. You don't have to lay out memory, declare variables and such. No tedious bookkeeping.
Python gives you a nice growth path. You can start off just writing script style programs, using the built in types like lists and dictionaries. Then you progress to using new modules as you need them, and advance into object-oriented coding using classes. There's some functional programming stuff in there too, which you can start learning once you have the basic mechanics of the language under control.
I just love visiting new parts of python all the time.
You can get a lot done in python. It comes with a whole lot of built in modules to do almost anything you like - email, web, xml, graphics, gui, etc.
:)
When I was learning to program in C, I found that Practical C Programming was a good resource. It's a very approachable book with lots of examples.
The fastest way in my view is through learn through websites.
Set a goal of what you want to do and start a simple project
Instead of reading too many books theoretically,google what you want to know to get it instantly as you go through your project.This way you get PRACTICAL knowledge.
Watch online videos as well.Check out my question on VIDEOS here
Ask whatever you don't understand on stackoverflow. We're here to help :)
Follow these steps and I can assure you that you will be a great programmer soon!
Cheers!
With others, I highly recommend Kernighan and Ritchie—perhaps the best language book ever written. I'd also recommend that you slow down and enjoy yourself: don't be wide and shallow; start out narrow and deep. If you like programming, you will want to master the craft rather than be in a hurry. This essay by Peter Norvig explains how not to be in such a rush.
P.S. I started programming at age 12 with APL/360. I had a blast and have been doing it ever since—35 years and counting. Good luck and don't forget to have fun!
By far the best way (and usually the fastest) to learn programming is to find a good mentor. That's easier said than done. But I think you'd be surprised how many people would be willing to help you out. My advice would be just don't be afraid to ask.
If I were you I would find a local FIRST robotics team and see if you can hang out for some of the coding. Odds are you'll be working on a similar problem and will have some support from people who have a decent amount of experience. That's what I would have done, anyway.
I started learning to program in Basic in about 1981 when I was 10. Not many years later it was 6502 assembly to try to get more speed out of a 1 MHz Apple IIe clone.
Pascal was a revelation in 1988 - programming without line numbers.
Modula-2, C, Eiffel, Miranda, Haskel, and Prolog at university as well as scripting in any number of languages.
C++ professionally for about 6 years.
C#, then Java, Ruby, and now back to C# for the last 18 months.
Python somewhere along the way.
My advice, pick the language that is best suited to the problem you need to solve today.
The first problem you have is to learn the basics ie how to break down a problem and express it in a clear and concise manner. I suggest you choose something other than C. I recommend Python as the online documentation is excellent and the libraries are great and you will spend more time writing interesting code and less time trying to figure out why your code stopped due to a segmentation fault.
When you've got the basic concepts under your belt, try some assembly and learn what's going on under the hood. If nothing else, you'll learn how fast CPUs really are. C is a good step after that. I also suggest you try Java or C# before Objective-C.
As to how long before moving to Objective-C, it really depends on how talented you are. If you're really good, then once you've learnt your 3rd or 4th language you'll can be more productive than most coders within 6 weeks of starting a new language (although changing language families (ie imperative, functional, object oriented) takes longer). If you're no good then don't expect to get past the first. Hopefully you make it into the first category.
In addition to whatever books and websites you end up using, you might consider looking around your area for local support groups. Many areas have a Linux user group or a group for Java or Ruby programming. Professional programmers use these groups to help each other with their programming problems, but the groups are generally friendly to young people and beginners. Don't feel embarrassed or awkward because of your age and inexperience. Most people will admire your initiative and curiosity and be happy to help you when you run into problems.
Assuming you have some basic programming knowledge, Cocoa Dev Central have a series of articles that explain basic C then Objective-C, in a somewhat-less-than-1000-pages way..
Learn C for Cocoa, then Learn Objective-C
Shouldn't take even an hour to go through. The articles don't cover anything remotely advanced, but if you're learning ObjC to write OS X applications, the ObjC bit is basically trivial, it's Cocoa that is difficult to learn!
If you want to learn Objectif-C to create iPhone application, don't waste your time on C and learn Objectif-C now, then a book on iPhone programming. It will be more than 1000 pages but if you want to program in your life, you have to be used to read these types of book.
I created an online interactive C tutorial, you can start using it without installing an IDE.
http://www.learn-c.org
While reading some programming books, I notice that the authors says that, in OOP, you may have some confusion while understanding the main idea of OOP.
And hell yeah!. I had some confusion. Did you have the same and what makes this confusion to programmers(even experienced programmers)?!
And if you had it, how could you beat this ?!
Thanks
The Animal trope works when explaining it to most people.
(Further useful links here and here)
A lot of the confusion when learning OOP comes from trying to pick the right relationship between objects and classes of objects, particularly whether:
Object contains Some other Object (or Object1 has an Object2)
Object is an instance of Class
If I can think of a good example that shows a case where either might be appropriate, I'll add it...
OOP takes a "problem oriented" approach to programming as opposed to the traditional "machine oriented" approach used in languages like C and Pascal. Learning OOP can be quite tough if you've programmed extensively in procedural/functional languages. It is to these programmers that things tend to be more confusing. If you are new to programming, you'll probably find things a lot less confusing since you're starting off with a fresh mind.
Having said that, I've seen many programmers who've worked extensively with languages like Java and claim to be good OOP programmers when they were actually far from it. Sure they use Java language features like interfaces, inheritance etc, and create objects "which are instances of classes", and "send a message to an object". Most people use a lot of OOP jargon because they are exposed to it. But when it comes down to writing a simple application their resulting code exposes their poor understanding.
My advise to you is don't get caught in using jargon alone. Question and learn the underlying concepts diligently. You might have your first semi-nirvana (like I did) when you learn polymorphism and the benefits it brings to code re-usability. Another semi-nirvana when you understand the trade-offs between reuse via inheritance and reuse via composition. In the end, you will know that you've understood OOP well if you able to design well, or rather, a good OO design is easily a good measure of how well you understand OOP.
If you are serious about OOP, you should read the first two chapters of the GOF book on Design Patterns. It might be a little tough on new programmers, but it lays the crux of the thinking behind OOP. This book is an important reference which any serious OOP programmer should have. If you understand the concepts in this book well, consider yourself to be a good OO programmer.
Yes, I experienced a bit of confusion initially. This was back in the day when OO was just starting to become mainstream, so there were a lot of books out there which covered it, but didn't explain it well for people who didn't already know what it was. As a result, I started out thinking that an object and a class were largely interchangeable and defining a new class for each object I wanted to create.
I finally "got it" by playing around on LambdaMOO, a MUD (think World of Warcraft, but with no graphics) with an object-oriented in-game programming language. Ironically, MOOCode makes no distinction between classes and objects - objects inherit directly from other objects. (It did have a convention of objects intended for use as "base classes" to be named "Generic Foo" as a way to distinguish them from specific ("instance") Foos, but that's as close to a class/object distinction as it had.)
Indeed, I think way too much emphasis is put on the 'class' concept.
The biggest leap forward in my understanding was when reading about the "Tell, don't Ask" principle.
I only started 'feeling' Object Orientation when playing around with (and reading about) duck-typed environments like Ruby, JavaScript, Python etc... after like 8 years happily creating truckloads of classes in C++.
Statically typed languages are great for production code, but you pay a lot of overhead when trying to get a feeling for Object Orientation.
Also, next to the commonly used term OOP, often one forgets that first comes OOA and OOD.
I think that especially programmers, that were experienced in the development with function-oriented languages, had trouble understanding the concepts of OOP. At least, it was really confusing to me and i did a whole bunch of things to program functional while using an OOP language(Java).
But i also think that the OOP approach is a great thing to beginners because this approach ist very "natural".
I never really had any confusion but I learned programming along the time-axis it evolved. so I had assembly, c, c++, java, c# and loads of other which is not relevant here. What you have to embrace is that everything shall be expressed by an object and an object contains information describing itself (properties) and that they can perform tasks related to them (methods i.E.: Car.GetAllCars();).
For inheritance and polymorphism and all the rest I recommend practice. practice everything - since practice makes perfect. Try to develop the examples given in all the books.
Once you understand the oo basics take a look at design patterns and design principles (e.g. by reading Head First Design Patterns). It will teach you how you should actually use the tools that oo gives you. While this is no substitute for practical experience it can certainly speed up the learning process.
Thank you for your answers.
I think giving examples works best but not every time, right ?!
I heared the creator of C++ when he said, it takes time and patience and you will understand it better by trying.
I've been studying OOP for quite a while now and I have a good grasp of the theory. I read the Head First book on OOP and, while it reinforced a lot of the theory, I found the case studies to be somewhat trivial.
I find that I'm applying OOP principles to my code each day, but I'm not sure if I'm applying them correctly. I need to get to the point where I am able to look at my code and know whether I'm using inheritance appropriately, whether my object is cohesive enough, etc.
Does anyone have any good recommendations (books, online guides, blogs, walk-throughs, etc.) for taking the next step in developing solid OOP skills?
I am working primarily in .NET (visual basic), but I welcome suggestions that incorporate various platforms.
Read Refactoring by Martin Fowler, and apply it to your own work.
It will take you through a litany of malodorous characteristics of software code that describe how to detect improperly constructed classes, and even more importantly, how to fix them.
Consider looking into Design Patterns. Although it seems like they aren't commonly used in enterprise applications (I've seen them more commonly used in API's and Frameworks than embedded into enterprise code), they could be applied to make software simpler or more robust in a lot of situations if only developers knew how to apply them.
The key is to understand the design patterns first, then with experience you'll learn how to apply them.
There is a Head First book on design patterns that teaches the concept pretty simply, although if you want a book that really covers design patterns in detail, check out the Gang of Four design patterns book, which is basically what made design patterns mainstream and is referred to almost every time the topic is brought up.
Design patterns can be applied in pretty much any object-oriented language to some degree or another, although some patterns can be overkill or over engineering in some cases.
EDIT:
I also want to add, you should check out the book Code Complete 2. It's a very influential book in the world of software development. It covers a lot of different concepts and theories. I learn something new every time I read it. It's such a good book that if I read it every 6 months to a year, I look at it from a different perspective that makes me a better programmer just by re-reading it. No matter how much you might think you know, this book will make you realize just how little you really know. It's really a great book. I can't stress how much you should own this book.
If you already have the basics, I believe only experience will get you further. You say you are not sure if you are applying the principles correctly, but there is no one correct way. Code you write today, you'll look at in 6 months time, and wonder why you wrote it that way, and probably know of a better, cleaner way of doing it. I also guarantee that after 10 years, you'll still be learning new techniques and tricks. Don't worry too much about it, it will come, just read as much as you can, and try and apply what you read in small chunks.
I am currently half-way through the following book:
http://www.amazon.com/Applying-UML-Patterns-Introduction-Object-Oriented/dp/0131489062
I cannot recommend this book strongly enough in terms of learning a real-life, professional-grade, practical approach to drafting and applying a well-formed and iterative design strategy before diving into code.
I, too, read the "Head First" book and felt that I was much better off for having read it.
After having a few years of working-world experience, I now view the Craig Larman book that I am recommending to be a perfect "next step" for me.
About the Presence of "UML" in this Book Title:
Whether you have positive feelings or negative feelings about UML notation, please do not let that influence your decision to buy the book (ISBN 0131489062) in either direction.
The prominence of "UML" in the title is misleading. While the author does use and explain UML notation, these explanations are extremely well-woven into relevant design discussions, and at no time does this book read like a boring UML spec.
In fact, here is a quote taken directly from the book:
What's important is knowing how to think and design in objects, which is a very different and much more valuable skill than knowing UML notation. While drawing a diagram, we need to answer key questions: What are the responsibilities of the object? Who does it collaborate with? What design patterns should be applied? Far more important than knowing the difference between UML 1.4 and 2.0 !
This book at times seems like it is "speaking to" a lead architect or a project manager. What I mean to say by that is that it assumes that the reader has significant control over the planning and direction of a software project.
Nonetheless, even if you are only responsible for some very small piece of your company's projects and products, I would still recommend this book and encourage you to apply some "scaled down" modifications of the book's advice to your piece of the project.
My OOP epiphany came from Grady Booch's book, way long time ago. Suddenly I realized why objects were good.
While polymorphism is cool, encapsulation is 75% of why objects are cool. It is sort of like an interface: you see the buttons but not the wiring. Before objects, only the most disciplined coders kept their grubby fingers off the internal bits of other people's procedures (it was called "structured programming").
Object make it easy to Do the Right Thing. Inheritance and polymorphism are little bonuses.
One way to learn about objects is to read other peoples' code. I learned a lot by reading the source code for the Delphi VCL framework. Even just looking at the documentation for Java will help you see what a single object class should do and how it is designed to be used by other objects.
Start a project of your own and pay attention when you want to sub-class your own classes and find that you have to go back and break up some protected methods so you can override just one piece of a process instead of replacing all of it. See how ancestors talk to descendants by calling abstract functions. In other words, go make a lot of mistakes and learn from them.
Enjoy!
Frankly, re-reading old David Parnas papers on information hiding helps me get in the right state of mind. The case studies may not be directly applicable but you should be able to get some useful generalizations out of them.
My epiphany happened when I tried to implement a very OO problem (dynamically and recursively building SQL statements) in VB6. The best way to understand polymorphism or inheritance is to need it and not be able to use it.
One thing that will definitely help you is working on a well-known, respected open source project. Either dig through the source code and see how things are done or try to make some additions / modifications. You'll find that there isn't one style or one right answer for most problems, but by looking at several projects, you'll be able to get a wide view of how things can be done. From there, you'll begin to develop your own style and will hopefully make some contributions to open source in the process.
I think you have to attempt and fail at implementing OO solutions. That's how I did it anyway. What I mean by fail is that you end up writing smelly code while successfully delivering a working solution. After it's written you'll get a feel for where things didn't quite feel right. You may have some epiphanies, and/or you may go and hunt for a slicker solution from other programmers. Undoubtedly you'll implement some variation of standard design patterns by accident. In hindsight, a light will click on (oh! so that's what a visitor is for), and then understanding will accelerate.
As others have said, I think tooling through some good OO open source code is a good idea. So is working with more experienced programmers who would be willing to critique your work. However understanding comes through doing.
You might want to try to read (and write) some Smalltalk for a while. Squeak is a free implementation that can show you the power of a fully object-oriented environment (unlike java or .net). All library code source is included. The language itself is incredibly simple. You'll find that java and c# are slowly adding the features well-known to Smalltalk since 1980.
Tortoise HG is extrodanarily well designed piece of OO open source software (written in Python).
If you already understand the basics, building something from scratch in a fully object oriented language will be a good step in fully understanding OOP software architecture. If you don't know Python, Python Essential Reference will take you through the language in full in a few days to a week.
After you understand the language take a look through the software above and you'll have all sorts of epiphanies.
To understand basically anything thoroughly, you need to have a decent knowledge of at least one abstraction level above and one level below it. In the case of OO, others have mentioned design patterns as the layer above OO. This helps a lot to illustrate why OO is useful.
As far as the layer below OO, try to play around with higher-order functions/late binding for a while and get a feel for how these relatively simple constructs are used. Also, try to understand how OO is implemented under the hood (vtables, etc.) and how it can be done in pure C. Once you grok the value of using higher order functions and late binding, you'll quickly realize that OO is just a convenient syntax for passing around a set of related functions and the data they operate on.