VARIANT-CPP

The VARIANT-CPP library is a simply library that offers a Variant::Value class that can be used to store variables of almost any type. This is useful for C++ programs that interact with technologies that are not strongly typed.

Currently, the value objects can represent either an integer, a string, a vector of variants or a string-indexed map of variants:

#include <variant.h>

int main()
{
    // construct value to be an integer
    Variant::Value value = 10;
    
    // it can switch type during its lifetime
    value = "we are now a string";
    
    // it can also be turned into a regular integer based array, where each
    // entry is also a variant
    value[0] = "abc";
    value[1] = 128;
    
    // or you can use it as a string indexed map to create an assoc array
    // (once again, the values are variants too, so can be of almost any type)
    value["key1"] = 123;
    value["key2"] = "abc";
    
    // because the values are variants, you can also nest [] operators:
    value["key3"][0] = 123;
    value["key3"][1] = "abc";
    value["key3"][2][0] = 0;
    
    // casting operators have been implemented, so once a value is stored
    // in a variant, you can assign it to a regular C++ variable, the value
    // object will do its best to convert it to an appropriate value
    int x = value;
    int y = value[2];
    std::string z = value["key"][0];
    
    // a value can also be constructed or updated with an initializer list
    // containing variants itself (that of course do not have to be of the
    // same type)
    value = {
        Variant::Value("Value at index 0"),
        Variant::Value(1)
    };
    
    // a value can be casted to a vector or a map
    std::vector<Variant::Value> vector = value;
    std::map<std::string,Variant::Value> map = value;
    
    // done 
    return 0;
}

INSTALLATION

After you've downloaded the source code, you should compile and install the library by running the following two commands. This works on all regular Linux platforms. VARIANT-CPP depends on the json-c library so make sure you have installed this library and the header files of it installed before you try to install this library.

make
sudo make install

If you encounter problems when compiling the software, you can make changes to src/Makefile. On top of this file the most important compile options are set and they can be easily changed.

To use the library, simply add '#include <variant.h>' on top of your C++ source file. Be aware that this is a C++11 library, so C++11 support should be enabled.

ABOUT

VARIANT-CPP library is created and maintained by Copernica (www.copernica.com). Do you appreciate our work and are you looking for other high quality solutions?

Then check out our other solutions:

• PHP-CPP (www.php-cpp.com)
• PHP-JS (www.php-js.com)
• Copernica Marketing Suite (www.copernica.com)
• MailerQ MTA (www.mailerq.com)
• Responsive Email web service (www.responsiveemail.com)