User experience for stepping through code in the debugger in Visual Studio Ultimate.
It displays the code of each of the methods you step into on a canvas with call lines between them, helping you keep track of the bigger picture as well as the details.
Debugger Canvas pulls together all the code along a call path into a single display for browsing and even editing. Instead of having to keep all the code in your head while you look at one file tab at a time, now you can see the entire path on the canvas, enabling you to more easily track the flow of control and data through your application. Below, you can see an example where we have stepped into the execution of the Add Item function of a website shopping cart. The functionality requires the coordination of several methods, and the canvas lets you see them side by side so that you can more easily find and fix bugs.
DebuggerCanvas
For more details
http://msdn.microsoft.com/en-us/devlabs/debuggercanvas
http://blogs.msdn.com/b/somasegar/archive/2011/06/13/debugger-canvas-on-devlabs.aspx
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