instantiation

问题 I'm trying to work out how to create objects, set fields for that object, and then add the object to a collection. Specifically, how can I create a $newPerson where the Name field is "joe" and with an array consisting of "phone1, phone2, phone3"? Similarly, "sue" has an array of "cell4 etc" and "alice" with her attributes, and so on. Ultimately, to put these three objects into an array of objects, $collectionOfPeople ? output: thufir@dur:~/flwor/csv$ thufir@dur:~/flwor/csv$ pwsh import.ps1

问题 I'm trying to work out how to create objects, set fields for that object, and then add the object to a collection. Specifically, how can I create a $newPerson where the Name field is "joe" and with an array consisting of "phone1, phone2, phone3"? Similarly, "sue" has an array of "cell4 etc" and "alice" with her attributes, and so on. Ultimately, to put these three objects into an array of objects, $collectionOfPeople ? output: thufir@dur:~/flwor/csv$ thufir@dur:~/flwor/csv$ pwsh import.ps1

问题 I'm trying to work out how to create objects, set fields for that object, and then add the object to a collection. Specifically, how can I create a $newPerson where the Name field is "joe" and with an array consisting of "phone1, phone2, phone3"? Similarly, "sue" has an array of "cell4 etc" and "alice" with her attributes, and so on. Ultimately, to put these three objects into an array of objects, $collectionOfPeople ? output: thufir@dur:~/flwor/csv$ thufir@dur:~/flwor/csv$ pwsh import.ps1

问题 It's an exercise from C++ Primer 5th Edition : Exercise 16.27: For each labeled statement explain what, if any, instantiations happen. If a template is instantiated, explain why; if not, explain why not. P.677 template <typename T> class Stack { }; void f1(Stack<char>); // (a) class Exercise { Stack<double> &rsd; // (b) Stack<int> si; // (c) }; int main() { Stack<char> *sc; // (d) f1(*sc); // (e) int iObj = sizeof(Stack< string >); // (f) } Below is what I tried: (a) Stack<char> is

问题 It's an exercise from C++ Primer 5th Edition : Exercise 16.27: For each labeled statement explain what, if any, instantiations happen. If a template is instantiated, explain why; if not, explain why not. P.677 template <typename T> class Stack { }; void f1(Stack<char>); // (a) class Exercise { Stack<double> &rsd; // (b) Stack<int> si; // (c) }; int main() { Stack<char> *sc; // (d) f1(*sc); // (e) int iObj = sizeof(Stack< string >); // (f) } Below is what I tried: (a) Stack<char> is

问题 Consider this code snippet, template<bool b> struct other { static const bool value = !b; }; template<bool b> struct test { static const bool value = b || other<b>::value; }; int main() { bool value = test<true>::value; } Do compilers instantiate other<true> in situations such as the above, when instantiating seems completely unnecessary? Or just because I've written the syntax other<b>::value , compilers must instantiate it regardless of the fact that it contributes absolutely nothing to the

问题 Consider this code snippet, template<bool b> struct other { static const bool value = !b; }; template<bool b> struct test { static const bool value = b || other<b>::value; }; int main() { bool value = test<true>::value; } Do compilers instantiate other<true> in situations such as the above, when instantiating seems completely unnecessary? Or just because I've written the syntax other<b>::value , compilers must instantiate it regardless of the fact that it contributes absolutely nothing to the

问题 I am currently making a text based adventure in Java for the purposes of using it a test platform, to try out new things I learn from this Java book I'm reading. I am now trying to declare an instance of a subclass (as the player is scripted to find it). The parent class is Item and it has two subclasses: Weapon and Armour . However, no matter which way I try and declare it in, the IDE I'm using (Eclipse) flags the line with the following error: No enclosing instance of type Item is

问题 I am currently making a text based adventure in Java for the purposes of using it a test platform, to try out new things I learn from this Java book I'm reading. I am now trying to declare an instance of a subclass (as the player is scripted to find it). The parent class is Item and it has two subclasses: Weapon and Armour . However, no matter which way I try and declare it in, the IDE I'm using (Eclipse) flags the line with the following error: No enclosing instance of type Item is

问题 I have an abstract base class called Base that other programmers are to write implementations for. In some other part of the application, I want to catch all implementations that have been written and construct a single instance of each. If this could be done with no additional instructions to others beyond "implement Base", that would be beautiful. However, the code I have below, requires that each implementation register itself. It also doesn't work. #include <iostream> #include <vector>