namespaces

问题 I am learning C++ and I can never tell when I need to use :: . I do know that I need to use std:: in front of cout and cin . Does this mean that inside of the iostream file the developers that created it made a namespace called std and put the functions cin and cout into the namespace called std ? When I created a new class that isn't in the same file as main() for some reason I must add :: . For example, if I create a class called A , why do I need to put A:: in front of a function that I

问题 I am learning C++ and I can never tell when I need to use :: . I do know that I need to use std:: in front of cout and cin . Does this mean that inside of the iostream file the developers that created it made a namespace called std and put the functions cin and cout into the namespace called std ? When I created a new class that isn't in the same file as main() for some reason I must add :: . For example, if I create a class called A , why do I need to put A:: in front of a function that I

问题 Closed. This question needs debugging details. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed last month . I have this error: 'someFunction' is not an exported object from 'namespace:somePackage' Does anyone know how to solve it? 回答1: Some reasons: Function is not part of the package, anymore, try ??someFunction to find out which package it belongs to. Package data is not part of the package Function is

问题 I'm working with XML document, where I edit text and attributes of tags, however I encountered a problem. ElementTree namespace registration does not work properly. The process is that I parse XML document, strip namespaces, register them in order to preserve them as the are on the input, make changes in some tags and then save(write) the final document. The problem is that it does not read all of the namespaces and edit them after saving. When I debug script, it shows however (as I believe),

问题 I am trying to create a model simulation using RxODE, this R-code was successful previously on a colleague's computer. R was just reinstalled on the computer I am currently using (version 3.6.2). I continue to get this error... Error: package or namespace load failed for ‘RxODE’: .onAttach failed in attachNamespace() for 'RxODE', details: call: !.rxWinRtoolsPath(retry = NA) error: invalid argument type I have tried .libPaths(.libPaths()[2]), reinstalling all my packages, and to install RxODE

问题 I have a problem with overloading operator<< combined with namespaces. I have read the related posts, but still do not understand what is going on in my case.. The following code compiles OK: file test_matrix.hpp: #ifndef TEST_MATRIX_HPP #define TEST_MATRIX_HPP #include <boost/numeric/ublas/matrix.hpp> #include <boost/numeric/ublas/matrix_expression.hpp> namespace ublas = boost::numeric::ublas; // shortcut name namespace VecMat { typedef ublas::matrix<double> MatrixD; // matrix of doubles

问题 I have PHP example on how to use Yelp Fusion API. It uses OAuth.php file with several classes. In main example it is imported with require_once('lib/OAuth.php'); Can I do the same in Laravel? Or I'd better provide namespace for OAuth.php file and put it somewhere on the tree? Where to put it? 回答1: I suggest your to make a new directory inside app and call it like "Classes" and store your OAuth.php as "/app/Classes/OAuth.php". Don't forget to put a namespace App\Classes; to top of this file.

问题 I need to be able to do this: $ns = "\\common\\components\\cfoBi\\i18n\\{$countryCode}\\gimmea"; use $USP; Obviously this won't work. So how can I do this? Have "dynamic namespaces"? 回答1: Not possible. Namespaces, imports and aliases are resolved at compile time. However, it is possible to create objects from a class name that is built at runtime: $className = "common\\components\\cfoBi\\i18n\\{$countryCode}\\gimmea"; $object = new $className(); See PHP docs: http://php.net/manual/en/language

问题 I have a kind: Namespace template yaml like follows, apiVersion: v1 kind: Namespace metadata: name: {{ .Values.namespace }} namespace: "" How do I make helm install create the above-given namespace ( {{ .Values.namespace }} ) if and only if above namespace ( {{ .Values.namespace }} ) doesn't exits in the pointed kubernets cluster 回答1: For helm2 it's best to avoiding creating the namespace as part of your chart content if at all possible and letting helm manage it. helm install with the -

问题 i have a question about enums that the codes are below: namespace space { public enum MyEnums { Enum1,Enum2,... } } namespace space { public class MyClass { public enum MyEnums { Enum1,Enum2,... } } } whats difference and how to use them? 回答1: Well syntactically the only difference is that you'd preface the enum type with the containing class: MyClass.MyEnums.Enum1 versus just MyEnums.Enum1 (in both cases the namespace is assumed to be covered with a using directive) However, containing it