I have a windows 32-bit dll written in C++ (probably C++ Builder). It has 1 function which I need to call:

int SPAPI_GetProduct(vector<SPApiProduct>& apiProdList)

I am stuck at the keyword vector.

How is it translated into free pascal?

Is the following correct?

type
    TSPApiProduct_Array = array of SPApiProduct;
function SPAPI_GetProduct(var apiProdList : TSPApiProduct);stdcall;

Thanks a lot in advance.

Dennis

I am stuck at the keyword vector. How is it translated into free pascal?

It's hard, you must create additional wrapper that exposes simpler type (pointer or array of pchar) OR make wrapper for the vector methods and simply declare it as an opaque pointer. std::vector is template/generic C++ class that implements a dynamic array functionality, but it can't be used outside C++.

In our previous episode, Dennis said:

It is not a keyword it is a generic type. So that is not easy, specially since C++ and Pascal classes differ.

And even if the call succeeds, getting results from apiprodlist is major problem number two.

You can try to match the C++ code with carefully crafted pascal code, but that requires knowledge about implementation details of the C++ implementaton.

I avoided that way (as too complicated and too fragile), but Rudy Velthuis has an article on it (C++ <-> Delphi)
http://www.rvelthuis.de/articles/articles-cppobjs.html

I myself generally solve this with a wrapper DLL, by crafting a DLL in C++ that exports a C (not C++) interface, and then use that. The same method as QT is used from Lazarus (via wrapper dll/.so qtpas)

leledumbo wrote

> I am stuck at the keyword vector. >> How is it translated into free pascal? It's hard, you must create additional wrapper that exposes simpler type(pointer or array of pchar) OR make wrapper for the vector methods andsimply declare it as an opaque pointer. std::vector is template/generic C++class that implements a dynamic array functionality, but it can't be usedoutside C++.

Would it be possible to do this via a Lua shim?

Thanks. I think I will follow your advice.

Dennis

Would it be possible to do this via a Lua shim?

How is it even related with that?

leledumbo wrote

> Would it be possible to do this via a Lua shim? How is it even related with that?

I thought FPC had the ability to execute a fragment of Lua, and Lua I believe can call C++ directly.

I thought FPC had the ability to execute a fragment of Lua, and Lua I

believe can call C++ directly.

No, Lua can only call C, just like FPC. You do know the problem of C++ interfacing, don't you?

leledumbo wrote

> I thought FPC had the ability to execute a fragment of Lua, and Lua Ibelieve can call C++ directly. No, Lua can only call C, just like FPC. You do know the problem of C++interfacing, don't you?

Yes, very much so. My apologies for my speculation generating noise.