operator-keyword

问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 8 years ago . There is an operator ? : in Java which can be used to select a value according to the boolean expression. For example, the expression

问题 #include<iostream> using namespace std; class complex { double real; double image; public: complex(double r=0,double i=0) : real(r), image(i) { }; complex(const complex& c) : real(c.real), image(c.image) { }; ~complex(){}; double re() const { return real; }; double im() const{ return image; }; const complex& operator =(const complex&c) { real = c.real; image = c.image; return *this; }; const complex& operator +=(const complex&c) { real += c.real; image += c.image; return *this; }; const

问题 Edit: This question is out of date as the Polyfill example has been updated. I'm leaving the question here just for reference. Read the correct answer for useful information on bitwise shift operators. Question: On line 7 in the Polyfill example of the Mozilla Array.prototype.indexOf page they comment this: var length = this.length >>> 0; // Hack to convert object.length to a UInt32 But the bitwise shift specification on Mozilla clearly states that the operator returns a value of the same

问题 I want to write a pointer in c++ (or in c++0x), that will points to a operator of a class lets say A or B. Is there any method to do it? Of course there is a syntax like int (A::*_p) (); but it doesn't solve this problem. I want to make general pointer, not specifying the base class for it - only pointer for "operator function" #include <thread> #include <iostream> using namespace std; class A { public: int operator()() { return 10; } }; class B { public: int operator()() { return 11; } };

问题 I'm trying to be lazy and implement the cast operators in the abstract base class rather than in each of the derived concrete classes. I've managed to cast one way, but I'm unable to cast the other. I think it might not be possible, but wanted to pick the collective SO mind before giving up: public interface IValueType<T> { T Value{ get; set; } } public abstract class ValueType<T> : IValueType<T> { public abstract T Value { get; set; } public static explicit operator T(ValueType<T> vt) { if

问题 I write code below: let array1: [Int] = [0,1] let array2 = array1 + [2] It just works.I want to find where + operator define. I search ArrayExtension in my workspace without result.I search Apple doc Collection Sequence Array , there is no result. Is there a way to navigate to operator definition ,like CMD + CTRL + J for func 回答1: You can select the operator in the Xcode source editor, and choose "Navigate -> Jump to definition" from the menu, or press CMD+CTRL+J. (This was broken in Xcode 10

问题 enter image description hereI have created a code to help me retrieving the data from csv file import re keywords = {"metal", "energy", "team", "sheet", "solar" "financial", "transportation", "electrical", "scientists", "electronic", "workers"} # all your keywords keyre=re.compile("energy",re.IGNORECASE) with open("2006-data-8-8-2016.csv") as infile: with open("new_data.csv", "w") as outfile: outfile.write(infile.readline()) # Save the header for line in infile: if len(keyre.findall(line))>0:

问题 This function is preventing Wagic: the homebrew from Compiling: /home/white/Pandora/wagic-read-only/projects/mtg/src/GameOptions.cpp:1156: error: no match for ‘operator>>’ in ‘s >> local’ Source(GameOptions.cpp): http://code.google.com/p/wagic/source/browse/trunk/projects/mtg/src/ GameOptions.cpp Source(General): http://code.google.com/p/wagic/source/browse/ (Line 1142-1172) bool GameOptionKeyBindings::read(string input) { istringstream iss(input); vector<pair<LocalKeySym, JButton> > assoc;

问题 In C#, what's the difference between A::B and A.B ? The only difference I've noticed is that only :: can be used with global , but other than that, what's the difference? Why do they both exist? 回答1: with :: you can do things like... extern alias X; extern alias Y; class Test { X::N.A a; X::N.B b1; Y::N.B b2; Y::N.C c; } and there are times when . is ambiguous so :: is needed. here's the example from the C# language spec namespace N { public class A {} public class B {} } namespace N { using

问题 I'm trying to implement my own boolean class, but cannot replicate native semantics for &&. The following contrived code demonstrates the issue: #include <iostream>> class MyBool { public: bool theValue; MyBool() {} MyBool(bool aBool) {theValue = aBool;} MyBool operator&& (MyBool aBool) {return theValue && aBool.theValue;} }; bool f1() {std::cout << " First\n"; return false;} bool f2() {std::cout << " Second\n"; return false;} int main(int argc, char** argv) { std::cout << "Native &&\n"; f1()