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Android – Listen For Incoming SMS Messages
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use Intents.SMS_RECEIVED_ACTION instead of the hard-coded one.
– Ahmad Kayyali
Dec 3 '13 at 7:13
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c++ boost::multi_index composite keys efficiency - c++1y / stl - 清泛IT社区，为创新赋能！
...e. sorting is performed by the first key, then the second key if the first one is equal, etc". Does this mean that the structure is stored such that a lookup for a specific 2-part composite key will take O(n=1) time, i.e. is the container sorted such that there is a pointer directly to each ite...
Standard concise way to copy a file in Java?
...py a file in Java involves opening streams, declaring a buffer, reading in one file, looping through it, and writing it out to the other steam. The web is littered with similar, yet still slightly different implementations of this type of solution.
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How to pass objects to functions in C++?
... as a std::optional (boost::optional for older std libs), and aliasing is done fine by reference.
C++11's move semantics make passing and returning by value much more attractive even for complex objects.
Rules of thumb for C++03:
Pass arguments by const reference, except when
they are to be change...
#ifdef replacement in the Swift language
...ta and a different way of processing it. I have two environment variables: one which, when switched on, tells the app to generate the fake data from the real data while running on my device; the other which, when switched on, uses the fake data (not the missing music library) while running on the Si...
CocoaPods - use specific pod version
...ing', '1.2.0'
Check 'Get started' at http://cocoapods.org
Once this is done, you can then issue a pod update in the terminal for the change to take place. Of course, this needs to be done from your project's top level folder. If the update does not occur, edit your Podfile.lock file and change ...
Why is “if not someobj:” better than “if someobj == None:” in Python?
...est, Python try to convert the object to a bool value if it is not already one. Roughly, we are asking the object : are you meaningful or not ? This is done using the following algorithm :
If the object has a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method...
Validate uniqueness of multiple columns
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You can use validates to validate uniqueness on one column:
validates :user_id, uniqueness: {scope: :friend_id}
The syntax for the validation on multiple columns is similar, but you should provide an array of fields instead:
validates :attr, uniqueness: {scope: [:attr1...
What is the correct answer for cout
... the calls you expained it would be undefined behaviour. But now, I have one more question (may be siller one, and I missing something basic and thinking loud) How did you deduce that the global version of std::operator<<() would be called instead of ostream::operator<<() member versi...
A Java collection of value pairs? (tuples?)
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The Pair class is one of those "gimme" generics examples that is easy enough to write on your own. For example, off the top of my head:
public class Pair<L,R> {
private final L left;
private final R right;
public Pair(L left, R ...