当我重新加载我的包时，这个异常未被捕获：
Error: EISDIR: illegal operation on a directory, read
at Object.readSync (fs.js:592:3)
at tryReadSync (fs.js:366:20)
at Object.readFileSync (fs.js:403:19)
at UnableToResolveError.buildCodeFrameMessage (/home/brady/obs-websocket-app/node_modules/metro/src/node-haste/DependencyGraph/ModuleResolution.js:347:17)
at new UnableToResolveError (/home/brady/obs-websocket-app/node_modules/metro/src/node-haste/DependencyGraph/ModuleResolution.js:333:35)
at ModuleResolver.resolveDependency (/home/brady/obs-websocket-app/node_modules/metro/src/node-haste/DependencyGraph/ModuleResolution.js:211:15)
at DependencyGraph.resolveDependency (/home/brady/obs-websocket-app/node_modules/metro/src/node-haste/DependencyGraph.js:413:43)
at /home/brady/obs-websocket-app/node_modules/metro/src/lib/transformHelpers.js:317:42
at /home/brady/obs-websocket-app/node_modules/metro/src/Server.js:1471:14
at Generator.next (<anonymous>)
我的 package.json
{
"main": "src/index.js",
"scripts": {
"android": "react-native run-android",
"ios": "react-native run-ios",
"web": "expo start --web",
"start": "react-native start",
"test": "jest"
},
"dependencies": {
"@types/node": "^14.14.35",
"events": "^3.3.0",
"expo": "~40.0.0",
"expo-splash-screen": "~0.8.0",
"expo-updates": "~0.4.0",
"obs-websocket-js": "^4.0.2",
"react": "16.13.1",
"react-dom": "16.13.1",
"react-native": …我正在使用OpenGL,我需要将VertexShader.glsl的内容放入std :: string中
我已经查看了相关的StackOverflow帖子,但我真的不知道如何将数据类型和内容匹配在一起以使其工作.
以读取文件内容为例,将其转换为C++中的字符串
#include <fstream>
#include <string>
int main(int argc, char** argv)
{
std::ifstream ifs("myfile.txt");
std::string content( (std::istreambuf_iterator<char>(ifs) ),
(std::istreambuf_iterator<char>() ) );
return 0;
}
我不知道之后发生了什么
std :: string内容
每次我使用std :: string之前都是这样的
std::string name = "2bdkid";
这是 CMake 输出：
-- The C compiler identification is MSVC 16.0.30319.1
-- The CXX compiler identification is MSVC 16.0.30319.1
-- Eclipse version is set to 3.6 (Helios). Adjust CMAKE_ECLIPSE_VERSION if this is wrong.
-- Check for working C compiler: C:/Program Files (x86)/Microsoft Visual Studio
10.0/VC/bin/amd64/cl.exe
-- Check for working C compiler: C:/Program Files (x86)/Microsoft Visual Studio
10.0/VC/bin/amd64/cl.exe -- broken
CMake Error at C:/Program Files (x86)/CMake/share/cmake-3.2/Modules/CMakeTestCCompiler.cmake:61 (message):
The C compiler "C:/Program Files (x86)/Microsoft Visual Studio 10.0/VC/bin/amd64/cl.exe" is not able to compile …来自First Principles的Haskell练习说要实现filter使用foldr,这就是我想出的,但它感觉和看起来很笨重.是否有更自然的方式来实现它foldr？
import Data.Bool
myFilter :: (a -> Bool) -> [a] -> [a]
myFilter f = foldr (\x -> bool (++ []) ((:) x) (f x)) []
我正在阅读有关NVI Idiom 的内容，大多数示例都遵循这种形式
#include <iostream>
class Base {
public:
virtual ~Base() = default;
void do_something() {
do_something_impl();
}
private:
virtual void do_something_impl() = 0;
};
class Derived : public Base {
private:
void do_something_impl() override {
std::cout << "Hello, world!\n";
}
};
void foo(Base& b) {
b.do_something();
}
int main() {
Derived d;
foo(d);
}
我一直认为“类的私有成员只能由该类的成员和朋友访问”（来自cppreference），在do_something_impl中实现时Derived，是否不考虑访问说明符？或者是Derived会员Base？实现虚函数不算“访问”吗？我不确定语言的哪一部分允许这样做。
这是我的代码：
struct Server<'a> {
port: &'a u16,
}
impl Server {
fn connect() {
//stuff
}
}
我收到的错误与impl块有关：
error: wrong number of lifetime parameters: expected 1, found 0 [E0107]
我必须添加一个生命周期参数以Server允许u16切片，但我不知道如何为impl块添加一个。
在C++中,我可以将1000个数组int放到堆上,如下所示:
int size = 1000;
int* values = new int[size];
delete[] values;
我无法弄清楚如何在Rust中执行等效操作.
let size = 1000;
let values = Box::new([0; size]) // error: non-constant path in constant expression
根据我的理解,Rust强制在编译时知道所有数组的大小,并且在创建数组时不允许使用表达式.
所以我理解s2绑定到表达式s1 + s1,但是当时评估的是这个,s2还是懒惰并在s2 += "Test";被调用时进行评估？还会s2为临时字符串保存内存吗？
#include <iostream>
#include <string>
int main()
{
std::string s1 = "Test";
std::string&& s2 = s1 + s1;
s2 += "Test";
std::cout << s2 << '\n';
}
这段代码:
fn ackermann(m: i32, n: i32) -> i32 {
if m == 0 {
return n + 1;
} else if m > 0 && n == 0 {
return ackermann(m - 1, 1);
} else if m > 0 && n > 0 {
return ackermann(m - 1, ackermann(m, n - 1));
}
}
编译时出错:
error: mismatched types [--explain E0308]
--> src/main.rs:3:5
|>
3 |> if m == 0 {
|> ^ expected i32, found ()
note: expected type …project(Brendan-C-SFML)
cmake_minimum_required(VERSION 2.8)
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "$ENV{SFML_ROOT}/cmake/Modules")
find_package(SFML REQUIRED COMPONENTS main system window graphics audio)
add_executable(Brendan-C-SFML brendan-c.cpp)
target_include_directories(Brendan-C-SFML PRIVATE ${SFML_INCLUDE_DIR})
target_link_libraries(Brendan-C-SFML ${SFML_LIBRARIES})
我有一个share文件夹,它应该在同一个目录中,Brendan-C-SFML.exe但是CLion构建了源代码,因此share无法访问.有没有办法将CLion设置为复制share到构建目录？