Can I extract function arguments from a function pointer?

Can I extract extra information (like number of arguments and their types) from a function pointer? If (most likely) not, what is the best way to allow a programmer to pass in a function pointer and the variable number of arguments EDIT: I meant that it should allow functions with different number of arguments that it takes while making sure that the programmer does not pass incorrect argument types.

What I want to do: Expose functions and its arguments to scripting language without having a programmer to type the arguments out manually (and therefore allowing mistakes to occur where the programmer passes the function pointer and the incorrect arguments that the function takes in).

A little more clarification: I should be able to output the function name and the argument types for documentation purposes.

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开发者_StackOverflow社区

James's answer is what I was looking for. Here is the code as it is a bit convoluted that should help anybody stuck in the same situation.

boost::function_traits<boost::remove_pointer
                         <BOOST_TYPEOF(&SomeFunction)>::type>::arg2_type);

If you require output, use RTTI (assuming you have RTTI enabled in compiler)

std::cout << typeid(boost::function_traits<boost::remove_pointer
    <BOOST_TYPEOF(&SomeFunction)>::type>::arg2_type).name() << std::endl;

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You can get the arity, return type, and parameter types of a function using function_traits from the Boost.TypeTraits library.

To fully enable your described scenario of having what is effectively a variadic function that is type safe, you really need variadic templates, a new feature being added in C++0x and supported by some recently released compilers (e.g., Clang, gcc). If you need something more extensive, you will probably need to implement your own runtime type system.

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I'm not entirely clear what you're after, but boost.function_types can tell you the return type, number of arguments, and argument types of a function pointer.

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You may want to consider using the Boost::Function library and Boost::TypeTraits. I find Boost::Function makes function pointers easier to deal with and allows you to use function objects in a generic way (i.e. you are not constrained by the type of the function object which is a pain), which are all round much nicer than raw function pointers

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You could probably convert doxygen xml output into the proper declarations/metadata for your scripting language. The information in this other question might get you started. Otherwise SWIG might help you, it's designed for generating cross-language wrappers, and can probably generate them compatible with your scripting language of choice.