std Questions

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I'm learning to program my Arduino, but I have a pretty solid background in C++, which means that I was very disappointed to find that I couldn't use the C++ Standard Library. I've been looking aro...
Stokeontrent asked 29/4, 2013 at 10:23

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I am new to std::thread. I need to put a std::thread to sleep from another thread, is that possible? In examples, all I see is code like: std::this_thread::sleep_for(std::chrono::seconds(1)); But ...
Emergent asked 12/10, 2012 at 12:55

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I compiled & installed gcc4.4 using macports. When I try to compile using -> g++ -g -Wall -ansi -pthread -std=c++0x main.cpp...: #include <thread> ... std::thread t(handle); t.join(...
Budgerigar asked 25/3, 2010 at 21:39

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I'm looking for a simple way to tokenize std::string input without using non default libraries such as Boost, etc. For example, if the user enters forty_five, I would like to separate 'forty' and '...
Revolute asked 7/4, 2012 at 4:14

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I'm implementing an iterator that iterates over the results of a generator function rather than over a data structure in memory such as a vector or map. Reading through the final working draft for...
Smug asked 8/10, 2017 at 1:52

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Title. I am implementing this class: #include <span> #include <vector> class MyClass { public: std::span<int *> numbers(void) { return m_numbers; } std::span<const int *&...
Gans asked 16/10, 2023 at 13:44

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I am trying to update some older code to the coming C++20 language using current GCC10. I was not able to update some templates because they used a std::enable_if<std::is_enum_v<T>> co...
Heshum asked 18/5, 2020 at 17:8

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I have some strings read from the database, stored in a char* and in UTF-8 format (you know, "á" is encoded as 0xC3 0xA1). But, in order to write them to a file, I first need to convert them to ANS...
Arturo asked 10/7, 2013 at 5:2

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I don't understand why in foobar below I need to specify std::vector<int>{} whereas in foobar2 I do not: #include <iostream> #include <memory> #include <vector> #include &lt...
Hydrotropism asked 30/9, 2023 at 0:56

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All I want to do is to check whether an element exists in the vector or not, so I can deal with each case. if ( item_present ) do_this(); else do_that();
Listel asked 20/2, 2009 at 21:58

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Why should I prefer one or another in practice? What are the technical differences except that std::thread is a class?
Unwearied asked 30/10, 2012 at 7:3

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C++ primer, 5th, 14.8.2, Using a Library Function Object with the Algorithms: vector<string *> nameTable; // vector of pointers // error: the pointers in nameTable are unrelated, so < is u...
Forearm asked 13/3, 2017 at 11:33

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I think it is confusing that there is no parallel version of std::accumulate in the C++ standard. It appears to me that it would be trivial to implement it in parallel, for instance, based on OpenM...
Selfpronouncing asked 6/9, 2023 at 0:19

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std::byte is an abstraction that is supposed to provide a type safe(r) access to regions of memory in C++, starting with the new standard 17. However, it's declared this way according to http://en....
Churr asked 12/6, 2017 at 20:27

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On CppCon 2022 was announced, that new official HelloWorld in C++ is now: #include <print> int main() { std::print("Hello world\n"); return 0; } Do you know, is std::print avail...
Malefactor asked 24/8, 2023 at 7:49

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Background: I'm trying to port a library to compile on MSVC. That library stores data in a tuple of vectors (std::tuple<std::vector<Ts>...>), and uses a custom iterator to iterate over ...
Maples asked 17/8, 2023 at 13:24

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I'm encountering an issue while compiling the following C++ code that utilizes the <chrono> library: #include "log.hpp" #include <chrono> #include <iomanip> #include &lt...
Plover asked 8/8, 2023 at 11:49

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I tried these codes, to compare std::copy and std::string's constructor. #include <chrono> #include <iostream> #include <vector> void construct_test() { std::vector<uint8_t&g...
Neonatal asked 8/8, 2023 at 9:29

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What does the phrase std::string::npos mean in the following snippet of code? found = str.find(str2); if (found != std::string::npos) std::cout << "first 'needle' found at: " << int(...
Inga asked 30/9, 2010 at 5:12

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I'm trying to use a std::string as a key in a std::map however, i'm unable to find() correctly. My code is somewhat complicated and large so this is a small program that demonstrates the problem I'...
Facies asked 4/12, 2011 at 10:54

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How can I use a std::valarray to store/manipulate a 2D array? I'd like to see an example of a 2D array with elements accessed by row/column indices. Something like this pseudo code: matrix(i,j) =...
Faroff asked 2/2, 2010 at 20:57

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In std::sort you can supply a third argument which is the basis for how it sorts a list. If you want the first argument to come first, then you return true. If you want the second argument to come ...
Merat asked 29/8, 2017 at 1:37

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I need a filesystem library for use with a C++11-capable compiler or a C++14-capable one - so it can't be be from C++17. Now, I know that the filesystem library going into C++17 is based based on...
Illyes asked 30/11, 2016 at 22:17

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This may just be a simple mistake that I'm not seeing, but I think I'm simply doing something wrong. Don't worry I'm not using namespace std in my header functions or anything which seemed to be ...
Branton asked 7/8, 2012 at 20:44

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C is somewhat, not exactly, a subset of C++. So we can use most of the C functions/headers in C++ by changing the name a little bit (stdio.h to cstdio, stdlib.h to cstdlib). My question is actual...
Holograph asked 16/9, 2015 at 10:26

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