Learning C++ as a Perl programmer

Question

I'm a Perl5 programmer for 7 years and I'm trying to learn C++ now. Some of the C++ syntax is hard for me to understand and to think in C++ way.

For example: In Perl, you can mix the data in the arrays

@array = (1,"string",5.355);

You can assign any value to a scalar variable:

$var = 1;
$var = "string";
$var = \$reference_to_scalar;

There are many examples.

A friend of mine recommend me the book "Thinking of C++" by Bruce Eckel, but I haven't any C background and it's hard for me to understand some things.

So my question is - could you recommend me a book for this situation. I don't want to learn C. I understand OOP (I'm getting more familiar with C++ oop aswell), I understand the point of the pointers (and some arithmetic) and references (widely used in Perl).

I don't need manuals for dummies (what is int, bool, double, if, while), I just need a direction how to learn C++ from the perspective of a Perl programmer, because I'm sure that there are many like me.

Thank you in advance.

EDIT: Thank you for all the recommended books and the answers, I will try with "Accelerated C++". I will start from the beginning and try to change my mindflow to C++. I have added the "beginner" tag.

Answer 1

"C++ For Perl Programmers" is a pretty specific request. Given that Perl abstracts away more of the machine than C++ does, I think that a good way to start would be to forget what you know about Perl and get a regular C++ book.

For example, it seems reasonable to you that you should be allowed to have multiple data types in an array, because a Perl array is a higher-level construct than just a series of contiguous words in memory. If I were going to go from an array in C++ to one in Perl, I would say that a Perl array is like a C++ array that holds pointers to data instead of data (if that is even true - I am not a Perl programmer so it may not be. Maybe a Perl array is more like a linked list data structure. In any case, you get the idea.) Going backwards, IMO, is not quite the same.

As far as the book I'd recommend - there are a lot of good ones, so it depends on the style and depth you're looking for. I think Accelerated C++ is great for ramping up - its thorough and covers a lot of ground without inundating you with the tedious details.

Answer 2

My university recommended us this book : http://www.lrde.epita.fr/~akim/ccmp/assignments.html#C_002b_002b-Primer

Anyway, Thinking in C++ is available on the web for free. You could find the link on the previous link I gave you.

Good luck :)

Answer 3

Here you can find a vast variety of free downloadable/online books.

Answer 4

I second Thinking In C++. I read it after knowing perl, and I found it very good. The second edition doesn't assume C knowledge; here's what it says under Prerequisites in the Preface:

In the first edition of this book, I decided to assume that someone else had taught you C and that you have at least a reading level of comfort with it. My primary focus was on simplifying what I found difficult: the C++ language. In this edition I have added a chapter that is a rapid introduction to C, along with the Thinking in C seminar-on-CD, but I am still assuming that you already have some kind of programming experience. In addition, just as you learn many new words intuitively by seeing them in context in a novel, it’s possible to learn a great deal about C from the context in which it is used in the rest of the book.

As danben said, you pretty much just need to "forget what you know about perl". It's useful to know perl just because it's another programming language (C-like, even), but it's nowhere near similar enough to just "learn the differences".

Also: Thinking In C++ is free for the electronic version.

Answer 5

Actually, since you already know an imperative language, learning C won't take you much time at all. The basics are all the same -- if statements, while loops, for loops etc. Even the way the namespaces are organized are similar (although the guts of course are different.) You might want to gloss over some of the pointer handling, as C++ does references a little differently, but you would not be doing yourself any harm by picking up and reading through a copy of K&R (the official C reference) at least once. (Every decent programmer should have a copy on his bookshelf as a reference, anyway.)

After that, pick up a recent edition of Stroustrup and have at it, ensuring that you work through the exercises. Some of the concepts may be a little foreign to a Perl-oriented mind, but it won't be too strange. If you encounter a particular concept you find tricky, post again on SO and there will be lots of people happy to go through it with you!

Answer 6

I would actually try to go from Perl to C first. C is a much simpler language, and many of the concepts will transfer to C++.

Answer 7

I tried to learn C++ from the "Thinking in C++" book. I found it very, very hard to learn from.

A much better book for someone starting in C++ is "Accelerated C++: Practical Programming by Example" by Andrew Koenig and Barbara E. Moo

Answer 8

The Stroustrup book is a little hard when learning the language, its better to try another book and use the Stroustrup book as a reference.

Answer 9

Don't bother with learning C unless you want to know C. Programming in C++ is nothing at all like programming in C. I realize most books and teachers claim otherwise, but they're wrong. You should be looking for the exceptions, such as the previously mentioned, "Accelerated C++."

You won't find any books that will help you write code like the code you've just shown. Perl is a very weakly typed language and C++ is exactly the opposite: a strongly typed language. There are, however, ways to get kind of what you're showing in your post in various boost constructs such as variant and tuple.

I would suggest though learning C++ as a totally independent language before stepping into that kind of thing. Don't learn C++ as a Perl Programmer, learn it as a complete newb. You may be bored with the first few chapters but in the end you'll have a better grasp of the style and powers unique to C++ vs. those unique to Perl. I haven't seen any "Xlanguage for Ylanguage" book that will get you there.

Answer 10

I've gone through the opposite process. One of the first things I learned was that while you can write Perl code that looks like C or C++, you shouldn't. The same goes for you. You can probably find a way to write Perl-ish C++ code, but don't bother. The languages are too different. You need to learn how to write C++ code as a C++ programmer. Several goods books have already been suggested. I think you should augment that by finding a mentor. You'll get immediate feedback if you're doing things the right or wrong way. You can also check out the C++ FAQ Lite, especially chapters 28 and 29 on issues for new C++ programmers.

The biggest difference is that C++ is strongly typed. Every variable has a type, and it doesn't change. Your example Perl code is technically possible in C++, but it requires an extra library that I'm not sure you're ready for yet. Instead, the C++ way is to think about a collection of mixed but related items as their own new type - a struct or class.

Another great option is to post specific C++ questions here on SO. I think we've been using the beginner tag for that. We don't discourage those questions as long as they're clearly worded.

Answer 11

I work with Perl exclusively for my day job and program C++ for fun on nights and weekends. They require totally different mind sets. You're better off approaching C++ as a noob programmer and learn it from 'Hello World' on up. Sure you can fast track over general concepts such data types, but still pay enough attention to know your short from your long and your reference from your pointer.

I would avoid learning C first unless you really need to know C. Character handling in C is a pain and not suited for what I suspect you want to do. The String class in C++ is your friend: learn it, live it love it!