Recent questions tagged C++

0 votes

213 views

1 answer

c++ - Named? parameters in templates, functions

Is there any update in the upcoming C++0x standard on named parameters in templates and/or functions? For example, I ... in main: f(arg_3: 55); See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

165 views

1 answer

c++ - Determining the Parameter Types of an Undefined Function

I've recently learned that I cannot: Take the address of an undefined function Take the address of a ... how decltypeargs could be crafted? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

314 views

1 answer

c++ - Embedded Database in Qt

I have a SQLite database for my Qt application. I assume that it would be logical to add the database as ... .ui RESOURCES += assets.qrc See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

275 views

1 answer

c++ - Why does std::is_const<const int&>::value evaluate to false?

This is a spin off of the question How to check if object is const or not?. I was surprised to see the ... const int& as a non-const type? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

191 views

1 answer

c++ - limits and uses of C++20 template lambas

A couple of related questions for C++ standard gurus. The incoming C++20 introduces template lambdas (P0428R2). So ... ; but it doesn't work. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

241 views

1 answer

c++ - Find the list of member variables of a class and their types?

I haven't ever heard it's possible, but asking with the hope that it might. For a class with many more member ... . So shouldn't it be possible? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

182 views

1 answer

c++ - Pointer-to-member confusion

I'm trying to understand the consistency in the error that is thrown in this program: #include <iostream> class A ... precedence of :: before &? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

623 views

1 answer

c++ - CMake build multiple targets in different build directories

I have the following CMake structure: CMakelists.txt toolchain.cmake folder1 ----CMakelists.txt folder2 ---- ... like this is possible? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

182 views

1 answer

c++ - What is the purpose of creating object files separately and then linking them together in a Makefile?

When using the gcc compiler, it will link and compile in one step. However, it appears to be idiomatic to turn ... reason(s) for this practice? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

164 views

1 answer

c++ - Assigning a vector of one type to a vector of another type

I have an "Event" class. Due to the way dates are handled, we need to wrap this class in a "UIEvent" class ... (and vice versa)might be best. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

303 views

1 answer

c++ - The indices of non-zero bytes of an SSE/AVX register

If an SSE/AVX register's value is such that all its bytes are either 0 or 1, is there any way to efficiently ... But that will lead to a loop. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

281 views

1 answer

c++ - Template Argument Deduction Broken in Clang 6 for Temporary Objects

Template argument deduction appears to be broken in Clang 6 for temporary objects. g++ 8.1.0 compiles and runs the example ... (1,"foo"s,2); } See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

155 views

1 answer

c++ - Order of function call

for the expression (func1() * func2()) + func3() will func1() * func2() be evaluated first as it has brackets ... and then (func1() * func2()) See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

741 views

1 answer

c++ - std::unordered_map very high memory usage

Yesterday i tried to use std::unordered_map and this code confused me how much memory it used. typedef list<string ... Why so much memory used? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

431 views

1 answer

c++ - Why doesn't void{} exist?

I am wondering why void() is a prvalue of void but void{} does not exist...? See the following answer: https:// ... R foo(){ return R{}; } See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

343 views

1 answer

c++ - Why is my union's size bigger than I expected?

When I print the size of a union like this: union u { char c[5]; int i; } un; using this: int _tmain(int argc ... ; why are there 6fs at un.c[3] See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

513 views

1 answer

c++ - error C2804: binary 'operator +' has too many parameters (compiling with VC 120)

Writing my own vector class (for a game engine) and overloading '+' operator in Visual Studio 2013 CPlusPlus ... overload non-member function. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

191 views

1 answer

c++ - Qt - Error 2 at compile time

I just downloaded Qt SDK 4.8.1 and, after installing it, I simply tried to compile a default C++ project, ... to cl in the project settings. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

315 views

1 answer

c++ - How can this code be constexpr? (std::chrono)

In the standards paper P0092R1, Howard Hinnant wrote: template <class To, class Rep, class Period, class = enable_if_t ... What's up with that? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

194 views

1 answer

c++ - typedef and incomplete type

Recently I am having many problem with typedef and incomplete type when I changed certain containers, allocators in ... design as a solution. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

237 views

1 answer

c++ - Why does decay to pointer for array argument appear not to apply to sizeof()?

I read a question earlier that was closed due to being an exact duplicate of this When a function has a ... without really thinking about it. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

330 views

1 answer

c++ - -x link flag causing link errors on Mac OSX 10.9 (bug?)

According to ld man pages, the -x link flag suppresses putting non-global symbols into the output file's symbol ... using the -x link flag? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

203 views

1 answer

c++ - Can't compile boost/any_iterator.hpp in boost 1.57

After (attempting to) upgrade a VS2012 project to use boost 1.57, I can no longer compile--lots and lots of ... Is anyone aware of a workaround? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

215 views

1 answer

c++ - g++ "is not a type" error

Writing a templated function, I declared: template <typename T> T invertible(T const& container, T::size_type startIndex ... ' is not a type See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

272 views

1 answer

c++ - What do linkers actually do with multiply-defined `inline` functions?

In both C and C++, inline functions with external linkage can of course have multiple definitions available at ... between them in this aspect. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

553 views

1 answer

c++ - Conversion from STL vector of subclass to vector of base class

I am wondering if it is possible to convert a vector of derived class values to a vector of base class values ... to a vector of pointers. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

303 views

1 answer

c++ - Runtime process memory patching for restoring state

I'm looking for a method for storing the process memory, and restore it later at certain conditions. ... Actually ... it could be useful to me. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

464 views

1 answer

c++ - Qt (Creator) with WinSocks (ws2_32)

I want to use an older code-fragment in my Qt-project, which is using WinSocks. I created my program with Qt Creator ... I don't want to use it. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

Categories

Just Browsing Browsing

Most popular tags