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Common elements comparison between 2 lists

...hereas the list comprehension method preserves the order. Important if anyone needs to consider this. Thanks. – agftrading Oct 1 '18 at 15:35  |  ...
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In a PHP project, what patterns exist to store, access and organize helper objects? [closed]

....html http://googletesting.blogspot.com/2008/08/where-have-all-singletons-gone.html Alternatives a service provider http://java.sun.com/blueprints/corej2eepatterns/Patterns/ServiceLocator.html dependency injection http://en.wikipedia.org/wiki/Dependency_injection and a php explanation: http:/...
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Integer.toString(int i) vs String.valueOf(int i)

... of doing the same thing. It may be a historical reason (can't remember if one came before the other). share | improve this answer | follow | ...
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Polymorphism in C++

...at when the type of data you're processing has a .size() member you'll use one function, otherwise another function that doesn't need .size() (but presumably suffers in some way - e.g. using the slower strlen() or not printing as useful a message in the log). You can also specify ad-hoc behaviours ...
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How do I replace NA values with zeros in an R dataframe?

...lue 0. These leaves all of the non-NAs as they were, and only replaces the ones with missingness. – Twitch_City Jul 29 '15 at 16:14 3 ...
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Setting an object to null vs Dispose()

...isposal from garbage collection. They are completely separate things, with one point in common which I'll come to in a minute. Dispose, garbage collection and finalization When you write a using statement, it's simply syntactic sugar for a try/finally block so that Dispose is called even if the c...
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How do I make a textbox that only accepts numbers?

...xtbox control that I want to only accept integer values. In the past I've done this kind of validation by overloading the KeyPress event and just removing characters which didn't fit the specification. I've looked at the MaskedTextBox control but I'd like a more general solution that could work with...
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Why .NET String is immutable? [duplicate]

...formance win in the case in question). With mutable objects that can't be done. No side-effects can come from passing an immutable type as a method to a parameter unless it is out or ref (since that changes the reference, not the object). A programmer therefore knows that if string x = "abc" at the ...
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Remove all classes that begin with a certain string

...ant to be able to clear all classes with a given prefix and then add a new one. If I want to remove all of the classes that begin with "bg", how do I do that? Something like this, but that actually works: ...
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Database cluster and load balancing

...e servers so the load is as evenly distributed as possible. It is usually done at the application layer (or with a connection pool). The only direct relation between replication and load balancing is that you need some replication to be able to load balance, else you'd have a single server. ...