move | 易学教程

std::move Vs std::forward

阅读更多关于 std::move Vs std::forward

问题 This seems to be most relavant question already asked. Whats the difference between std::move and std::forward But each answer is different and applies and says slightly different things. So I am confused. I have the following situation. Copy item into container The Copy item is C++03 so I understand that quite well. Construct item into container The Construct item into container I believe uses perfect forwarding correctly to forward the arguments through two functions to the constructor of T

How To Move (Drag and Drop) multiple Shapes with D3

阅读更多关于 How To Move (Drag and Drop) multiple Shapes with D3

How do I move (drag and drop) multiple shapes with d3. I tried putting some shapes in a svg and move the svg - this works but not smoothly. This is what I got so far <html> <head> <script type="text/javascript" src="d3.v3.min.js"></script> <title>Creating SVG groups with D3.js</title> </head> <body> <script type="text/javascript"> // http://tutorials.jenkov.com/svg/g-element.html d3image = d3.select("body"); svgcanvas = d3image.append("svg:svg").attr("width", 700).attr("height", 500); svg1 = svgcanvas.append("svg:svg").attr("x", 100).attr("y", 100); circle1 = svg1.append("svg:circle") .attr(

Draw line and move it programmatically

阅读更多关于 Draw line and move it programmatically

问题 I want to draw a line on a WPF Grid. private void InitializeTestline() { testline = new Line(); grid.Children.Add(testline); testline.X1 = 0; testline.X2 = 1; testline.Y1 = 0; testline.Y2 = 1; testline.HorizontalAlignment = System.Windows.HorizontalAlignment.Left; testline.VerticalAlignment = System.Windows.VerticalAlignment.Top; testline.Stroke = Brushes.Red; testline.Stretch = Stretch.Fill; testline.StrokeThickness = 2; testline.Visibility = System.Windows.Visibility.Visible; } It is drawn

What makes moving objects faster than copying?

阅读更多关于 What makes moving objects faster than copying?

问题 I have heard Scott Meyers say " std::move() doesn't move anything" ... but I haven't understood what it means. So to specify my question consider the following: class Box { /* things... */ }; Box box1 = some_value; Box box2 = box1; // value of box1 is copied to box2 ... ok What about: Box box3 = std::move(box1); I do understand the rules of lvalue and rvalue but what I don't understand is what is actually happening in the memory? Is it just copying the value in some different way, sharing an

Possible to move the tmp directory of Eclipse?

阅读更多关于 Possible to move the tmp directory of Eclipse?

I'm trying to speed up Eclipse by having my projects on a RAM disk (stuck with a slow laptop and a heavy kind of eclipse project at the moment). Worked great for loading the project and such, but when I'm building it seems to read and write a lot to a directory in %APPDATA% (seems to have a generated name from the name of the project). This makes it actually go slower than usual... So... is there a way I can move the tmp directory of eclipse? Preferably without moving the tmp directory of other applications in the process. May have found a way by setting a property called java.io.tmpdir in

std::move with std::make_pair

阅读更多关于 std::move with std::make_pair

Is there any difference between: std::map <int,std::pair<T,T>> m; T t1,t2; m.emplace(1,std::make_pair(t1,t2)); and: std::map <int,std::pair<T,T>> m; T t1,t2; m.emplace(1,std::move(std::make_pair(t1,t2))); Is the std::move redundant here? Will std::map::emplace and perfect forwarding take care of allocating the std::pair directly in the std::map ? std::make_pair(...) and std::move(std::make_pair(...)) are both rvalue expressions (the first one is a prvalue, the second one is an xvalue). Since emplace takes forwarding references, both are deduced as the same type, so std::move in this case is

Powershell: Move Files recursively

阅读更多关于 Powershell: Move Files recursively

I am trying to copy all build output files and folders into a Bin folder ( OutputDir/Bin ) except of some files which stay in the OutputDir . The Bin folder will never be deleted. Initial condition: Output config.log4net file1.txt file2.txt file3.dll ProjectXXX.exe en foo.txt fr foo.txt de foo.txt Target: Output Bin file1.txt file2.txt file3.dll en foo.txt fr foo.txt de foo.txt config.log4net ProjectXXX.exe My first try: $binaries = $args[0] $binFolderName = "bin" $binFolderPath = Join-Path $binaries $binFolderName New-Item $binFolderPath -ItemType Directory Get-Childitem -Path $binaries | ? {

Javascript move multiple elements to separate div's and back

阅读更多关于 Javascript move multiple elements to separate div's and back

问题 There are 3 videos, placed in 3 separate div's. There also are 3 separate div's, but in other position of a page (lets say contA and contB and contC). I want that if I click on the video1, then video2 and video3 goes to contA and contB, and video1 goes to contC. If I click video1 again, all videos go back to their original position. If I click on video2 (while its in contA), then video1 goes to contA, video3 goes to contB, video2 goes to contC. I have prepared a jsbin demo: Jsbin DEMO Anyone

smoothing mouse movement

阅读更多关于 smoothing mouse movement

问题 I'm developing a software to move the mouse based on certain coordinates which i get from a depth image from kinect. but I have 30 frames/second(images/second) and those coordinates changes with every frame so the mouse keeps moving. My question is,Is there a way to smooth the movement of the mouse ? 回答1: Yes you can start tracking with some parameters that allows you to make move smoother. Below is an example code: var parameters = new TransformSmoothParameters { Smoothing = 0.2f, Correction

Resize on std::vector does not call move constructor [duplicate]

阅读更多关于 Resize on std::vector does not call move constructor [duplicate]

This question already has answers here : Closed 4 years ago . C++11 rvalue reference calling copy constructor too (4 answers) I have been playing around with std::vector to understand when objects are constructed, destructed, copy constructed and move constructed. To so do, I have written the following program #include <iostream> #include <vector> class Test { public: Test() { std::cout << "Constructor called for " << this << std::endl; } Test(const Test& x) { std::cout << "Copy Constructor called for " << this << std::endl; } Test(Test&& x) { std::cout << "Move Constructor called for " <<