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Which is preferred: Nullable.HasValue or Nullable != null?
... (assuming some foos in the collection can be null too), we end up with at least three way to write our function (if we use C# 6) :
public IEnumerable<Foo> GetNonNullFoosWithSomeDoubleValues(IEnumerable<Foo> foos)
{
return foos.Where(foo => foo?.SomeDouble != null);
return ...
Fastest way to replace NAs in a large data.table
...place C function that updates NA by reference in the vector. That would at least halve the 20 seconds I think. Does such a function exist in any R package?
The reason f_andrie fails may be because it copies the whole of dt1, or creates a logical matrix as big as the whole of dt1, a few times. The o...
How to programmatically send SMS on the iPhone?
...MS from the iPhone itself, it requires some user interaction. But this at least allows you to populate everything, and avoids closing the application.
The MFMessageComposeViewController class is well documented, and tutorials show how easy it is to implement.
iOS 5 Update
iOS 5 includes messagin...
Quick-and-dirty way to ensure only one instance of a shell script is running at a time
.../1/flock which appears from the man copyright date to have around since at least 2006. So I made a downvote (-1), nothing personal, just have strong conviction that using the kernel implemented tools provided by the kernel developers is correct.
– Craig Hicks
...
Purpose of Trigraph sequences in C++?
...
As I recall, at least one compiler I've used (g++ ?) requires an explicit command line option before trigraph and or digraph is translated, otherwise a warning is given but no substitution.
– KTC
Aug 5 ...
Can't specify the 'async' modifier on the 'Main' method of a console app
... @abatishchev You should be using try/catch in your code, at least inside the Task.Run if not more granularly, not letting exceptions float up to the Task. You'll avoid the wrap up problem by putting try/catch around things that can fail.
– Chris Moschini
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Animate change of view controllers without using navigation controller stack, subviews or modal cont
...nimations that replace a view w/ a different view must occur with views at least a level below the first view added to the window (e.g. window.rootViewController.view.anotherView).
I've implemented a simple container class I called TransitionController. You can find it at https://gist.github.com/13...
What is the point of the diamond operator () in Java 7?
... that it does matter to use the diamond operator instead of a raw type, at least when arguments with generic bounds are being passed in.
– Paul Bellora
Mar 17 '13 at 1:29
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Iterate over object attributes in python
...This is a bad idea, I wouldn't even suggest it, but if you're going to, at least provide the caveat.
– Julian
Jul 24 '12 at 18:57
2
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proper hibernate annotation for byte[]
...the problem is that I don't know what the problem is exactly. But I can at least say that nothing has changed since 3.5.0-Beta-2 (which is where a changed has been introduced)in the 3.5.x branch.
But my understanding of issues like HHH-4876, HHH-4617 and of PostgreSQL and BLOBs (mentioned in the ja...