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A migration to add unique constraint to a combination of columns
...fme.com, "There are 46,427 people named John Smith" in the United States alone. That's about 127 years of days. As this is well over the average lifespan of a human being, this means that a DOB clash is mathematically certain.
All I'm saying is that that particular combination of unique fields cou...
Convert date to datetime in Python
... the minimum value representable by datetime and then getting its time component. Incidentally, datetime.min = datetime(MINYEAR, 1, 1, tzinfo=None) and has a time of 00:00:00. However, I think it is cleaner to explicitly create a 00:00:00 time either through time.min or time(0, 0, 0, 0).
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Horizontal ListView in Android?
Is it possible to make the ListView horizontally? I have done this using a gallery view, but the selected item comes to the center of the screen automatically. I don't want the selected item at the same spot I clicked. How can I rectify this problem? My idea was to set the ListView with a horizo...
How to pick a new color for each plotted line within a figure in matplotlib?
...: [colormap(i) for i in np.linspace(0, 0.9, num_plots)], where colormap is one of the colormaps in matplotlib.pyplot.cm and numplots is the number of unique colors that you want. Beware that this can result in colors that are hard to distinguish from each other, though!!
– Joe...
How do I keep the screen on in my App? [duplicate]
For my Android app I never want the phone to lock or the back light to turn off
11 Answers
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Thread-safe List property
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Even as it got the most votes, one usually can't take System.Collections.Concurrent.ConcurrentBag<T> as a thread-safe replacement for System.Collections.Generic.List<T> as it is (Radek Stromský already pointed it out) not ordered.
But there i...
How to copy an object in Objective-C
...tate, other objects, etc, and often make assumptions that they're the only ones holding references to that data. Bitwise copies break this assumption.
A deep, logical copy. In this, we make a copy of the object, but without actually doing it bit by bit - we want an object that behaves the same for a...
Difference between “module.exports” and “exports” in the CommonJs Module System
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Why!? Why one can read this only here. This should be tagline for every modular javaScript. Thanks
– lima_fil
Jan 23 '15 at 23:06
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What is the meaning of addToBackStack with null parameter?
I have a customer code. There is only one activity for all of the fragments i.e. the single activity is managing all the fragments.
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Shall we always use [unowned self] inside closure in Swift
...he previous answers don't really give straightforward rules on when to use one over the other and why, so let me add a few things.
The unowned or weak discussion boils down to a question of lifetime of the variable and the closure that references it.
Scenarios
You can have two possible scenarios:
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