How to declare array of strings & types <C++11

[h4ever]

For Visual Studio 2010 I need to create two arrays which will be saved in class.
One array should contain strings like

// declaration:
const char* predefinedArgs;
// implementation:
this->predefinedArgs[] = { "Jan", "Feb", "Mar", "April", "May", "June", "July", 
    "Aug", "Sep", "Oct", "Nov", "Dec" };

(this code does not work) Also I cannot to join it to one line because I don't use C++11.

And the second array which I need is to create array of times int and double
something like

const char* predefinedArgTypes;
// implementation:
this->predefinedArgTypes[] = { int, int, int, int, double, double, int, 
    int, int, int, int, std::string }; // the last one is just example for string 

How to solve it?

[MrHutch]

Sounds like you want a dynamic array in the first instance. I'd suggest using the standard library vector and string types.

Unfortunately, if you're pre-C++11 then you don't have initialiser list support, so you'd not be able to do it in a one-er. You can create a vector with an initial set of values from an array pretty easily, though:

#include <iostream>
#include <vector>
#include <string>

int main() 
{
    // C++11 (no auto here as we'll get const char* instead of std::string)
    std::vector<std::string> someStrings = { "Here", "Are", "Some", "Strings" };
    
    for (const auto& s : someStrings)
    {
        std::cout << s << std::endl;
    }
    
    // C++98
    typedef std::vector<std::string> TStringVector;
    std::string stringsAsArray[] = { "Some", "Other", "Strings" };
    std::vector<std::string> someOtherStrings (stringsAsArray, stringsAsArray + sizeof(stringsAsArray) / sizeof(stringsAsArray[0]));
    
    for (TStringVector::const_iterator it = someOtherStrings.begin(); it != someOtherStrings.end(); ++it)
    {
        std::cout << *it << std::endl;
    }
    
    return 0;
}

The second isn't possible - you can't mix types in arrays/containers.

[h4ever]

However it is not possible to declare zero size array like this

header:

std::string predefinedArgs[]; // cannot declare
nor this
std::string stringsAsArray[] = { "Some", "Other", "Strings" }; // this one is declaration + initiation 

// header
I can do this:
std::string predefinedArgs[12]; // declare 

but not this:

// implementing constructor
this->predefinedArgs[12] = { "Jan", "Feb", "Mar", "April", "May", "June", "July", 
    "Aug", "Sep", "Oct", "Nov", "Dec" };

error: : 'Wrapper::{ctor}' : constructors not allowed a return type

[MrHutch]

Which is why I recommend using a vector. Otherwise you have to start dynamically allocating your arrays.

Assuming you're creating some class: https://ideone.com/K8UCir

Edit: At this point I also feel obligated to share my feelings on how terrible I think the VS compiler is (very) and how much better life is when you migrate to a competent one (clang).

[h4ever]

I am not able to use your vector example. In VS2010, the second example not the C++11. I am separating into header and cpp

Because I cannot do this
std::string stringsAsArray[] = { "Some", "Other", "Strings" };
must separate to header and cpp

I can do it in main:

int main(int argc, char ** argv)
{	
	int aaa = CV_MINOR_VERSION;
	std::string stringsAsArray[] = { "Some", "Other", "Strings" };
return 0;
}

BUt this is not what I wanted. Get rid of it from here and move it to .h and .cpp into a class
How to do it?

I could also move it to global scope:

std::string stringsAsArray[] = { "Some", "Other", "Strings" };

int main(int argc, char ** argv)
{	

But that is wrong practice.

[MrHutch]

See the above IDE one link (which uses a std::string array).

Also, it's totally possibly to do with vectors. Just not in a one-liner initialiser list.

[h4ever]

Anyhow thanx, if you do not have perfect solution I will use global.

[Cubbi]

error: : 'Wrapper::{ctor}' : constructors not allowed a return type

based on that and some other hints (like the claim that "std::string stringsAsArray[] = { "Some", "Other", "Strings" };" does not compile), I am guessing that you need help writing a constructor that initializes a class member of type std::vector<std::string>.. but none of the code shown even shows a class, a constructor, or a member.

[jlb]

Is your array part of a class? If so do you want it to be const? If so then perhaps something like:

#include <string>
#include <iostream>
// Header file.
class Test
{
    public:
        static const std::string Args[] ;
};

// In your implementation file in the global scope.
const std::string Test::Args[] = {"string", "test"} ;


int main()
{
    Test my_test;

    for(int i = 0; i < 2; ++i)
        std::cout << Test::Args[i] << ", ";

    std::cout << std::endl;
}

Of course you'll need to include the proper header files in the appropriate files.

[h4ever]

I removed that error. It was from nowhere just sudden like a smack. I had to undo to remove that cr*p.

[h4ever]

The request is to separate it to declaration and to implementation.

std::string predefArgs[] = { "Some", "Other", "Strings" };

I cannot use it like this. I cannot to put it either to myclass.h nor to myclass.cpp
both will print error. Don't u use classes?

[jlb]

Don't u use classes?

Yes I use classes, however I'm not stuck in the past using C++98. I suggest you update your compiler and start using the current standards. Also you didn't really post enough code to decipher that you were using a class.

By the way the code I provided compiles with a C98 compiler.

[h4ever]

I cannot separate it. I use Windows XP that is Visual Studio. No update.

[jlb]

Why not? It works for me. Show exactly what you've tried.

I use Windows XP that is Visual Studio. No update.

Okay since you're using an outdated Operating system, your stuck with an outdated compiler, good luck.

[Cubbi]

h4ever wrote:

std::string predefArgs[] = { "Some", "Other", "Strings" };

I cannot use it like this. I cannot to put it either to myclass.h nor to myclass.cpp
both will print error.

As shown, it will "not print error" in any revision of C++. You're not showing enough code for anyone to reproduce the problem you're experiencing.

Don't u use classes

I *suspect* what is actually happening is you're trying to compile code like this:

#include <string>

class X {
   std::string predefArgs[] = { "Some", "Other", "Strings" }; // error
};

A C++98 version of that would be

#include <string>
#include <vector>
class X {
   std::vector<std::string> predefArgs;
   X() { 
       const char* init[] = { "Some", "Other", "Strings" };
       predefArgs.assign(init, init + sizeof init/sizeof *init);
   }
};

and given

h4ever wrote:

The request is to separate it to declaration and to implementation.

// myclass.h
class X {
   std::vector<std::string> predefArgs;
   X();
};

and

// myclass.cpp
X::X() { 
    const char* init[] = { "Some", "Other", "Strings" };
    predefArgs.assign(init, init + sizeof init/sizeof *init);
}

[h4ever]

I told you I am trying to separate declaration from implementation

so no

class X {
std::string predefArgs[] = { "Some", "Other", "Strings" }; // error
};

[MrHutch]

I'm not sure what more you want here. There have been solutions to your problem all through this thread.

Cubbi has given a perfectly succinct solution using vectors and a tidy way of initialising in your constructor. Not sure why you're not taking that.

If you're absolutely desperate to avoid vectors, I gave a solution in the fourth post that details how to do something similar with string arrays.

You seem to want a stack created array of strings that you can declare in one place, and implement in another in a one-liner. You can't. If you want this you need to heap allocate like I gave you in the example in the fourth post. If you want to stack create then you'll need to assign the string at each index individually - you cannot use an initialiser list.

My advice, aside from having a slightly better attitude towards those helping you, would be to take the eight lines of code offered by Cubbi at the end of his post that adequately solves your problem.