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Why do we need tuples in Python (or any immutable data type)?
...in particular, only immutables can be hashable (and, therefore, members of sets, or keys in dictionaries). Again, this afford optimization, but far more than just "substantial" (designing decent hash tables storing completely mutable objects is a nightmare -- either you take copies of everything as ...
Do Swift-based applications work on OS X 10.9/iOS 7 and lower?
...
Swift sets some bits in the Objective-C metadata to mark Swift classes. libobjc in OS X 10.9 and iOS 7.0 was changed to ignore these bits in preparation for Swift's arrival. Older OS versions will be confused by these bits.
...
Crash logs generated by iPhone Simulator?
...ically, open /Applications/Utilities/CrashReporterPrefs.app and change the setting to “Developer”. This will cause CrashReporter to display a popup with the crash log after your app crashes.
I found this in the “Viewing iOS Simulator Console and Crash Logs” section in this doc from Apple: ...
How do I set up a simple delegate to communicate between two view controllers?
...
While this covers how to setup a working Delegate protocol. I think it's ommiting a few key points. Firstly, when calling the methods on the delegate you should first be checking that the delegate responds to that selector. If it doesnt your app will...
Wait for a void async method
...
do a AutoResetEvent, call the function then wait on AutoResetEvent and then set it inside async void when you know it is done.
You can also wait on a Task that returns from your void async
...
DateTime.Now vs. DateTime.UtcNow
...@Jan Zich points out, It's actually a critically important property and is set differently depending on whether you use Now or UtcNow.
Internally the date is stored as Ticks which (contrary to @Carl Camera's answer) is different depending on if you use Now or UtcNow.
DateTime.UtcNow behaves like...
How to create Java gradle project
...s, java project has to be converted to the gradle project. Then, how can I set the source folders automatically?
– verystrongjoe
May 15 '15 at 0:26
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What C++ Smart Pointer Implementations are available?
...houldn't contain the same object. Assignment will transfer ownership and reset the rvalue auto pointer to a null pointer. Which leads to perhaps the worst drawback; they can't be used within STL containers due to the aforementioned inability to be copied. The final blow to any use case is they are s...
When should I use require() and when to use define()?
...efine'd module, or outside it? If it is used inside a module, why not just set the requirements in the module definition rather than use require?
– Petri
Jan 28 '14 at 6:48
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Only initializers, entity members, and entity navigation properties are supported
...ICollection
So instead of:
public class This
{
public long Id { get; set; }
//...
public virtual IEnumerable<That> Thats { get; set; }
}
Do this:
public class This
{
public long Id { get; set; }
//...
public virtual ICollection<That> Thats { get; set; }
}
A...