MinXL - Extending Excel for Mac with C++

Introduction

Excel for Windows has good support for interoperability with C++/C#; unfortunately the same cannot be said about Excel for Mac. MinXL aims to bridge that gap by allowing you to write functions in C++ and call them from VBA with a very intuitive API.

Although not header-only, MinXL is very simple to integrate. If you already have your project set up, just clone the repository into your dependencies folder and add it to your CMakeLists.txt file. MinXL is now header-only! Just add the include folder to your include paths, then #include <MinXL/MinXL.hpp> wherever you want to use it.

Requires C++20 (or later)

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Usage

On C++

#include <MinXL/MinXL.hpp>

// Extern C is not mandatory, but it makes importing functions on VBA much easier
// Alternatively, if you like suffering, you can import the function by its mangled name...
extern "C"
{
    // I strongly recommend receiving data using mxl::Variant&; a few extra bytes won't really matter
    // Primitive numeric types will work, but be aware of VBA's somewhat counter-intuitive naming
    // (e.g Longs have 4 bytes, Integers (and Booleans!!!) have 2 bytes, etc)
    mxl::Variant IncrementArrayBy(mxl::Variant& arg, double value)
    {
        try
        {
            // MinXL will automatically check if this conversion is valid
            mxl::Array<mxl::Variant> array = std::move(arg);

            // mxl::Variant has convenient operator overloads to make your life easier
            for (auto& i : array)
                i += value;

            // Implicitly converts back to mxl::Variant
            return std::move(array);
        }
        catch (mxl::Exception& e)
        {
            // If anything within the try block fails, MinXL will throw an exception with a
            // nice understandable message that can be returned as a string to Excel
            return mxl::String{e.what()};
        }
    }
}

On VBA

Private Declare PtrSafe Function IncrementArrayBy _
Lib "/Library/Application Support/Microsoft/YourLibrary.dylib" _
(ByRef v as Variant, ByVal d as Double) As Variant     ' Always pass Variants ByRef!

Public Function CallLibFunction(r as Range) as Variant
    CallLibFunction = IncrementArrayBy(r.Value2, 2.5)  ' Extract the Range's values first!!!
End Function

On Excel

In this example, not a single copy was performed inside C++ :D

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Contributions, questions and feedback

Contributions are welcome! Fork it, hack it and open a PR :)

This is still an early version and some limitations will be addressed over time.

If you have troubles and/or doubts while using MinXL, feel free to open an issue or message me directly at paulo.buenov@gmail.com.