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Multiple Inheritance in PHP

...tMessage class, and sending algorithm is delegated to dispatcher. This is called Strategy Pattern, you can read more on it here. share | improve this answer | follow ...
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static constructors in C++? I need to initialize private static objects

... to have a class with a private static data member (a vector that contains all the characters a-z). In java or C#, I can just make a "static constructor" that will run before I make any instances of the class, and sets up the static data members of the class. It only gets run once (as the variables ...
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What is Lazy Loading?

... It's called lazy loading because, like a lazy person, you are putting off doing something you don't want to. The opposite is Eager Loading, where you load something right away, long before you need it. If you are curious why peop...
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html5 localStorage error with Safari: “QUOTA_EXCEEDED_ERR: DOM Exception 22: An attempt was made to

...wsing mode, it appears as though localStorage is available, but trying to call setItem throws an exception. store.js line 73 "QUOTA_EXCEEDED_ERR: DOM Exception 22: An attempt was made to add something to storage that exceeded the quota." What happens is that the window object still exposes localS...
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Installing PDO driver on MySQL Linux server

... On Ubuntu you should be able to install the necessary PDO parts from apt using sudo apt-get install php5-mysql There is no limitation between using PDO and mysql_ simultaneously. You will however need to create two connections to your DB, one with mysql_ and o...
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Python 2.7: Print to File

... In Python 3.0+, print is a function, which you'd call with print(...). In earlier version, print is a statement, which you'd make with print .... To print to a file in Python earlier than 3.0, you'd do: print >> f, 'what ever %d', i The >> operator directs pr...
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Python None comparison: should I use “is” or ==?

...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects) In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity: lst = [1,2,3] lst == lst[:] # This is Tr...
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Check if a user has scrolled to the bottom

...ight of the visible window and checks if that equals the height of the overall content (document). If you wanted to instead check if the user is near the bottom, it'd look something like this: $(window).scroll(function() { if($(window).scrollTop() + $(window).height() > $(document).height() ...
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Error: No default engine was specified and no extension was provided

...err }); lines in your code with: res.json({ error: err }) PS: People usually also have message in the returned object: res.status(err.status || 500); res.json({ message: err.message, error: err }); share | ...
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MongoDB/NoSQL: Keeping Document Change History

... changes to one or more specific entities in a database. I've heard this called row versioning, a log table or a history table (I'm sure there are other names for it). There are a number of ways to approach it in an RDBMS--you can write all changes from all source tables to a single table (more of...