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Why covariance and contravariance do not support value type
...
Basically, variance applies when the CLR can ensure that it doesn't need to make any representational change to the values. References all look the same - so you can use an IEnumerable<string> as an IEnumerable<object>...
Visual Studio popup: “the operation could not be completed”
...ed in the solution file (like the starting project) and other things.
Normally you can delete the .suo file without problems. You might have to set the StartUp Project for your solution afterwards.
Just to stay on the safe way, you can rename the .suo file, and then retry to start the solution, to...
How to list containers in Docker
...o show only running containers use the given command:
docker ps
To show all containers use the given command:
docker ps -a
To show the latest created container (includes all states) use the given command:
docker ps -l
To show n last created containers (includes all states) use the given com...
Visual Studio “Find” results in “No files were found to look in. Find stopped progress.”
...o this thread:
Posted by Microsoft on 10/13/2009 at
4:33 PM
Hi all,
Thank you for your continued interest
in this bug. We have been able to
reproduce the issue intermittently in
several versions of Visual Studio
running on several versions of Windows
and have identified th...
Reverse Range in Swift
...o:0,by:-1) { print(i) } // 5 4 3 2 1
Update For latest Swift 2
First of all, protocol extensions change how reverse is used:
for i in (1...5).reverse() { print(i) } // 5 4 3 2 1
Stride has been reworked in Xcode 7 Beta 6. The new usage is:
for i in 0.stride(to: -8, by: -2) { print(i) } // 0 -2...
Open Graph namespace declaration: HTML with XMLNS or head prefix?
...icting information on how to best implement Open Graph namespaces. Specifically, the Open Graph website uses a few different methods, and the Facebook Open Graph examples use other methods.
...
Django development IDE [closed]
I have done a little Django development, but it has all been in a text editor. I was curious what more advanced development tools others are using in their Django development.
...
Google Maps API v3: Can I setZoom after fitBounds?
...ot on an embedded Google Map (API v3). I'd like the bounds to accommodate all points unless the zoom level is too low (i.e., zoomed out too much). My approach has been like this:
...
What are the differences between B trees and B+ trees?
... leaf node.
The leaf nodes of B+ trees are linked, so doing a full scan of all objects in a tree requires just one linear pass through all the leaf nodes. A B tree, on the other hand, would require a traversal of every level in the tree. This full-tree traversal will likely involve more cache misses...
How do you work with an array of jQuery Deferreds?
...data be loaded in a certain order: the root URL, then the schemas, then finally initialize the application with the schemas and urls for the various data objects. As the user navigates the application, data objects are loaded, validated against the schema, and displayed. As the user CRUDs the data...