https://www.postgresql.org/docs/7.2/libpqplusplus.html something like this?

Please provide a source

<quote>The begin iterator is not decrementable and the behavior is undefined if --container.begin() is evaluated.</quote> from https://en.cppreference.com/w/cpp/named_req/BidirectionalIterator That applies to C++17 and before. For C++20, <quote>A bidirectional iterator r is said to be decrementable if and only if there exists some s such that ++s == r.</quote> from https://en.cppreference.com/w/cpp/iterator/bidirectional_iterator To see why the post C++20 requirement is similar to the C++17 requirements (as in that it leads to UB), look at the requirements for the increment operator for a forward_iterator here - https://en.cppreference.com/w/cpp/iterator/forward_iterator. A forward_iterator is what the C++20 standard uses as a base for defining a bidirectional_iterator concept.

Add the following in your CMakeLists file find_package(CURL REQUIRED) include_directories(${CURL_INCLUDE_DIR}) target_link_libraries(<your executable name from add_executable> ${CURL_LIBRARIES})

set(SOURCE_FILES main.cpp) add_executable(aio_checker ${SOURCE_FILES}) find_package(CURL REQUIRED) include_directories(${CURL_INCLUDE_DIR}) target_link_libraries(${SOURCE_FILES} ${CURL_LIBRARIES}) Could NOT find CURL (missing: CURL_LIBRARY CURL_INCLUDE_DIR)

I don't know where to put it into...

Read this https://stackoverflow.com/questions/21314893/what-is-the-default-search-path-for-find-package-in-windows-using-cmake and then this https://cmake.org/cmake/help/latest/command/find_package.html

Is this correct to transfer shared_from_this() in destructor? class TSomeObject; using TSomeObjectSptr = std::shared_ptr<TSomeObject>; class TOwner { public: virtual ~TOwner(void) = default; virtual void open(const TSomeObjectSptr& ) = 0; virtual void close(const TSomeObjectSptr& ) = 0; }; class TSomeObject : public std::enable_shared_from_this<TSomeObject> { private: TOwner* m_pOwner; public: TSomeObject(TOwner* pOwner) : m_pOwner(pOwner) { m_pOwner->open(shared_from_this()); // OK } virtual ~TSomeObject(void) { m_pOwner->close(shared_from_this()); // Is this OK? } };

This should be ok as the actual destruction of the shared pointer will happen only after the close function finishes and since close takes a reference, it should be ok.

Clear, but I think that it isn't OK, if TOwner will save shared pointer and continue to use it after TOwner::close.

If that is the case then your interface doesn't reveal it. So you will have to specify it clearly in your question in that case. Even if TOwner saved the shared_ptr, it should do it by calling shared_from_this. If that is the case then it should still be ok

<quote>The begin iterator is not decrementable and the behavior is undefined if --container.begin() is evaluated.</quote> from https://en.cppreference.com/w/cpp/named_req/BidirectionalIterator That applies to C++17 and before. For C++20, <quote>A bidirectional iterator r is said to be decrementable if and only if there exists some s such that ++s == r.</quote> from https://en.cppreference.com/w/cpp/iterator/bidirectional_iterator To see why the post C++20 requirement is similar to the C++17 requirements (as in that it leads to UB), look at the requirements for the increment operator for a forward_iterator here - https://en.cppreference.com/w/cpp/iterator/forward_iterator. A forward_iterator is what the C++20 standard uses as a base for defining a bidirectional_iterator concept.

#include <iostream> using namespace std; int nextprime(int n); int main() { int n; cout << "Enter the no.: "; cin >> n; n = n + 1; cout<<nextprime(n); } int nextprime(int n) { bool found = true; int i; for (;; n++) { for (i = 2; i <= n / 2; i++) { if (n % i == 0) { found = false; break; } } if (found) return n; } }

Hi, how do I add libcurl to my Clion project?

Would compilers get that the arguments in order from the array?

you need to define an overload that accepts an std::initializer_list

maybe you could find this document useful: https://en.cppreference.com/w/cpp/utility/initializer_list

you need to define an overload that accepts an std::initializer_list

Not really. std::pair does not have a constructor which takes a std::initializer_list argument. @michelromero Look up "list initialization in C++" in your favourite search engine.

I think it's convenient, but maybe I shouldn't have used "need" in that sentence A constructor can also be used for brace initialization

std::initializer_list should be used to give priority to a special function during overload resolution when using the {...} syntax, so yeah, not really necessary, however it's a good practice if you want to be explicit in your definitions

maybe something like: template<typename T1, typename T2> class Pair { public: T1 first; T2 second; Pair(T1 first, T2 second) : first(first), second(second) {} }; can be called via Pair<int, int> p1 = {1, 2}; as well

It is actually the opposite and is not a good practice. A constructor taking a std::initializer list must be used only when absolutely necessary as this constructor can cause problems with its aggressive matching tendencies. Read Scott Meyers' Effective Modern C++ to understand why

This is what I called "list initialization" in my reply and asked the author to look it up.

that's the intention of declaring a std::initializer_list overload in first place. "aggressive matching tendencies," could you elaborate in that sentence? or to the page of the book you're referring to, if possible

a code snippet talks more than referencing people, i improved your reply with an example of what you meant

Which is why you should not use it for data structures like pair or tuple which are meant to emulate an aggregate data type despite having user provided/user declared constructors

If you look up "list initialization in C++" in Google like I suggested, there will be 1000s of snippets much better and much more in detail than the snippet you provided.

you provided none.

I would like to include libcurl into CMake, I am currently using Clion on Windows.. can anyone help me please?

is there any way to print like this using loops ? The sizeof(char) is : 1 bytes The sizeof(short) is : 2 bytes The sizeof(int) is : 4 bytes The sizeof(long) is : 8 bytes The sizeof(long long) is : 8 bytes The sizeof(float) is : 4 bytes The sizeof(double) is : 8 bytes The sizeof(long double) is : 16 bytes The sizeof(bool) is : 1 bytes

is there any way to print like this using loops ? The sizeof(char) is : 1 bytes The sizeof(short) is : 2 bytes The sizeof(int) is : 4 bytes The sizeof(long) is : 8 bytes The sizeof(long long) is : 8 bytes The sizeof(float) is : 4 bytes The sizeof(double) is : 8 bytes The sizeof(long double) is : 16 bytes The sizeof(bool) is : 1 bytes

you mean, iterating types?

How do you get the type sequence? from a tuple or from a vector of type_info?

yes

you tell , i am asking