Jens Seidel writes:

On Sun, Apr 20, 2008 at 03:35:27AM +0000, 7stud wrote:

...

Following the instructions in the tutorial, I installed boost in /usr/local as instructed, so my directory structure is:

/usr/local/boost_1_34_1/boost

I also tried to execute the program from the command line with the original include path:

#include

but I get the same error:

~/2testing/dir1$ g++ prog1.cpp prog1.cpp:1:35: error: boost/lambda/lambda.hpp:

You need of course to specify /usr/local/boost_1_34_1 as include path via -isystem /usr/local/boost_1_34_1 or -I /usr/local/boost_1_34_1 so that the compiler knows where to find boost header files.

Jens

Here is the tutorial example: #include #include <iostream> #include <iterator> #include <algorithm> int main() { using namespace boost::lambda; typedef std::istream_iterator<int> in; std::for_each(in(std::cin), in(), std::cout << (_1 * 3) << " " ); return 0; } And this is what happens: gcc -I /usr/local/boost_1_34_1 prog1.cpp /usr/bin/ld: Undefined symbols: std::basic_ios::operator void*() const std::basic_istream::operator>>(int&) std::basic_ostream::operator<<(int) std::ios_base::Init::Init() std::ios_base::Init::~Init() std::cin std::cout std::basic_ostream & std::operator<< (std::basic_ostream&, char const*) ___gxx_personality_v0 collect2: ld returned 1 exit status

Jens Seidel writes:

Please use the C++ compiler "g++" instead of the C compiler "gcc".

Whoops. Somewhere between my first post and my second post I began using the gcc command instead of the g++ command. The program compiles fine when I use the command: g++-I /usr/local/boost_1_34_1 prog1.cpp

...

/usr/bin/ld: Undefined symbols:

Ah, OK, now the compiler error vanished as the compiler is able to find the header files of boost.

[The following can probably be ignored as I missed at the beginning the you used the C compiler. Nevertheless you may find the next usful in you later steps:]

Now the linker complains about symbols (such as functions) defined in a Boost library which you have to link against.

You need for linking the additional options -L /usr/local/boost_1_34_1/lib/ (to specify the library search path) -l boost??? (to specify the library)

Sorry, I do not remember the library name which contains lambda. Just look into your /usr/local/boost_1_34_1/ for available dynamic lib/libboost*.so or lib/libboost*.a static libraries and choose the right one (without lib prefix or .so or a suffix).

Please note that this kind of question indicate that you are not very familiar with a C++ compiler.

You are right. I am not familiar with the gcc compilers. I've used MS VC++6 for about 10 years to write and compile C++ programs, but I recently switched from windows to a mac. Mac's have an IDE called Xcode for writing and compiling C++ programs, and that's what I've been using recently.

That's not a problem but please try to find such answers yourself by following more basic C++/g++ tutorials.

Starting with a simple "Hello world" program is typically the first step.

I can compile a 'hello' world problem using the command line, but that's about it.

On Sun, Apr 20, 2008 at 07:49:28PM +0000, 7stud wrote:

And when I try running the program in the Xcode 2.4 IDE, I get different errors. I added the directory /usr/local/boost_1_34_1 to the Project Settings under:

Project>Edit Project Settings Collection: Search Paths Header Search Paths /usr/local/boost_1_34_1/**

And when I run the program, I get an error for the line:

typedef std::istream_iterator<int> in;

which says:

error: expected initializer before token '<' token

It works for me. Please check that you use indeed a C++ compiler not a C one. Maybe adding (after all other #include-statements in the example) #include <iterator> helps to make this error go away?

And I get an error for the line:

std::for_each(in(std::cin), in(), std::cout << (_1 * 3) << " " );

which says:

error: for_each is not a member of 'std'

for_each is defined in algorithm which is included ... Try: #include <iostream> int main() { std::cout << "Hello World. This is my first C++ program\n"; return 0; } Jens

On Mon, Apr 21, 2008 at 01:36:41AM +0000, 7stud wrote:

Jens Seidel writes:

...

It works for me. Please check that you use indeed a C++ compiler not a C one.

Are you using Xcode?

Of course not! Please always restrict to free tools every person has access to. Xcode is probably not free otherwise I would find it in my Linux distribution. That's also the reason why you should always, again, always, start from the command line to understand the basic problems. Any kind of GUI (graphical environment) is an additional layer which requires that you have knowledge of the previous ones. Calling a compiler from the command line is the most basic stuff every coder has to know. Really.

I can't find a setting in Xcode for the compiler.

This doesn't matter. Any GUI related question should not be asked on this list. Can you again post your code together with the first (let's say 30) error lines? If it doesn't work it is maybe because the C++ compiler isn't properly installed? Please try also other examples of using boost. Sometimes a specific example of the Boost library is just faulty, yep, this happens. (In this case you shouldreport it, so that it can be fixed.) Jens

On Mon, Apr 21, 2008 at 09:09:06AM +0000, 7stud wrote:

Jens Seidel writes:

...

On Mon, Apr 21, 2008 at 01:36:41AM +0000, 7stud wrote:

...

Jens Seidel writes:

...

It works for me. Please check that you use indeed a C++ compiler not a C one.

Are you using Xcode?

Of course not! Please always restrict to free tools every person has access to. Xcode is probably not free otherwise I would find it in my Linux distribution.

Then don't respond to a post asking about Xcode by saying, "It works for me" !

The code works indeed for me and compiles cleanly (at least with g++ 4.1.2).

...

This doesn't matter. Any GUI related question should not be asked on this list.

This is a general boost users list, therefore I think it's appropriate to ask how boost interacts with IDE's.

No, as Boost is completely independent of any GUI. If you're not able to use a GUI don't use it! Jens

On 4/21/08 12:59 AM, "Jens Seidel" wrote:

Please always restrict to free tools every person has access to.

<snip>

Any GUI related question should not be asked on this list.

Discussion of tools related the use of Boost Libraries is appropriate for this list without regard to the nature of those tools. If you have questions or concerns about content of Boost-User postings, please address them to boost-users-owner@lists.boost.org, not to this list. Thanks to all for your understanding. And to all of you that, like Jens, help others by answering the questions posted here, a big on-going thank you. -- Jon Kalb Jon@KalbWeb.com Boost-Users moderator

Daniel James writes:

On 21/04/2008, 7stud wrote:

...

Are you using Xcode? I can't find a setting in Xcode for the compiler. When I create a new project, I choose Command Line Utility>C++ Tool. Then Xcode creates the project for me. I don't know what I should do to run the boost program in Xcode.

I don't normally use Xcode, but I had a quick look. If you start a C++ project, choose 'edit project settings' from the project menu then select the 'build' tab there are options for 'Header Search Paths' which is probably what you need to set. I expect you need to add '/usr/local/boost_1_34_1' to 'Header Search Paths'.

From one of my earlier posts:

---- And when I try running the program in the Xcode 2.4 IDE, I get different errors. I added the directory /usr/local/boost_1_34_1 to the Project Settings under: Project>Edit Project Settings Collection: Search Paths Header Search Paths /usr/local/boost_1_34_1/** And when I run the program, I get an error for the line: typedef std::istream_iterator<int> in; which says: error: expected initializer before token '<' token And I get an error for the line: std::for_each(in(std::cin), in(), std::cout << (_1 * 3) << " " ); which says: error: for_each is not a member of 'std' ----------