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What is the 'override' keyword in C++ used for? [duplicate]

... removed (not alternated). This is useful if the subclass is expecting a callback but it will never happen due to the library change, etc. – Hei Mar 11 '18 at 5:32 ...
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How to get a time zone from a location using latitude and longitude coordinates?

... zone from a location. This community wiki is an attempt at consolidating all of the valid responses. 17 Answers ...
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How to convert nanoseconds to seconds using the TimeUnit enum?

... This answer is now wrong - convert() and the toFoo() methods all return longs now docs.oracle.com/javase/6/docs/api/java/util/concurrent/… – Riking Jul 30 '13 at 1:58 ...
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How do I create a MongoDB dump of my database?

...ump: $ ./mongodump --host prod.example.com connected to: prod.example.com all dbs DATABASE: log to dump/log log.errors to dump/log/errors.bson 713 objects log.analytics to dump/log/analytics.bson 234810 objects DATABASE: blog to dump/blog ...
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How do I update/upsert a document in Mongoose?

... Mongoose now supports this natively with findOneAndUpdate (calls MongoDB findAndModify). The upsert = true option creates the object if it doesn't exist. defaults to false. var query = {'username': req.user.username}; req.newData.username = req.user.username; MyModel.findOneAndUpd...
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Compile time string hashing

... string length, and the compiler is not clever enough to elide the second call. Check other answers for possible fix for this problem. – CygnusX1 Feb 27 '16 at 16:34 ...
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Create a custom event in Java

...else in the package interface ThrowListener { public void Catch(); } /*_____________________________________________________________*/class Thrower { //list of catchers & corresponding function to add/remove them in the list List<ThrowListener> listeners = new ArrayList<ThrowLis...
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Selecting multiple columns in a pandas dataframe

...). df1 = df[['a', 'b']] Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead: df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...
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What does “abstract over” mean?

...the similarities. We say that we abstract over the differences, but this really means we're integrating by the similarities. For example, consider a program that takes the sum of the numbers 1, 2, and 3: val sumOfOneTwoThree = 1 + 2 + 3 This program is not very interesting, since it's not very a...
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Should I declare Jackson's ObjectMapper as a static field?

...hey are fully immutable, thread-safe, meaning that it is not even theoretically possible to cause thread-safety issues (which can occur with ObjectMapper if code tries to re-configure instance). share | ...