In Scheme you can use the dot notation for declaring a procedure that receives a variable number of arguments (also known as varargs or variadic function): (define (procedure . args) …) Inside procedure, args will be a list with the zero or more arguments passed; call it like this: (procedure “a” “b” “c”) As pointed … Read more
The value for a variadic argument can be specified either by enumerating the elements, or using an existing slice, specified by its name followed by …. You want to mix the 2 possible ways which is not permitted by the Go Language Specification (Passing arguments to … parameters). If the first form is used (enumerating … Read more
It is one of the punctuators. 6.4.6 Punctuators Syntax punctuator: one of [ ] ( ) { } . -> ++ — & * + – ~ ! / % << >> < > <= >= == != ^ | && || ? : ; … = *= /= %= += -= <<= >>= &= … Read more
I am not sure what your intention is but instead of storing it in a std::function you can use the lambda itself to capture the params. This is an example discussed on the boost mailing list. It is used in the boost::hana implementation auto list = [](auto …xs) { return [=](auto access) { return access(xs…); … Read more
A possible solution is to make the parameter type a container that can be initialized by a brace initializer list, such as std::initializer_list<int> or std::vector<int>. For example: #include <iostream> #include <initializer_list> void func(std::initializer_list<int> a_args) { for (auto i: a_args) std::cout << i << ‘\n’; } int main() { func({4, 7}); func({4, 7, 12, 14}); }
Here is my homework of the day, it’s based on macro tricks and today I particularly learnt about __VA_NARG__ invented by Laurent Deniau. Anyway, the following sample code works up to 8 fields for the sake of clarity. Just extend the code by duplicating if you need more (this is because the preprocessor doesn’t feature … Read more
I read answers and comments and I see that few things weren’t mentioned: data.frame uses list(…) version. Fragment of the code: object <- as.list(substitute(list(…)))[-1L] mrn <- is.null(row.names) x <- list(…) object is used to do some magic with column names, but x is used to create final data.frame. For use of unevaluated … argument look … Read more
If you don’t have a function analogous to vfprintf that takes a va_list instead of a variable number of arguments, you can’t do it. See http://c-faq.com/varargs/handoff.html. Example: void myfun(const char *fmt, va_list argp) { vfprintf(stderr, fmt, argp); }
C99 way, also supported by VC++ compiler. #define FOO(fmt, …) printf(fmt, ##__VA_ARGS__)
With params you can call your method like this: addTwoEach(1, 2, 3, 4, 5); Without params, you can’t. Additionally, you can call the method with an array as a parameter in both cases: addTwoEach(new int[] { 1, 2, 3, 4, 5 }); That is, params allows you to use a shortcut when calling the method. … Read more