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Proper use of beginBackgroundTaskWithExpirationHandler
... to start the network operation. If you just want an existing operation to complete, as per @Eyal's question, you don't need to do anything in applicationDidEnterBackground
– Ashley Mills
Aug 3 '12 at 20:03
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What is the exact problem with multiple inheritance?
...rom both A and B, but you don't override the doSomething method.
When the compiler seed this code...
C c = new C();
c.doSomething();
...which implementation of the method should it use? Without any further clarification, it's impossible for the compiler to resolve the ambiguity.
Besides overrid...
Why can't I define a static method in a Java interface?
...proposal to add them in Java 7, but it was later dropped due to unforeseen complications.
Finally, Java 8 introduced static interface methods, as well as override-able instance methods with a default implementation. They still can't have instance fields though. These features are part of the lambda...
Prefer composition over inheritance?
Why prefer composition over inheritance? What trade-offs are there for each approach? When should you choose inheritance over composition?
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What is the difference between 'git pull' and 'git fetch'?
... fetch periodically in a cron job in the background (although I wouldn't recommend doing this).
A git pull is what you would do to bring a local branch up-to-date with its remote version, while also updating your other remote-tracking branches.
From the Git documentation for git pull:
In its defaul...
What platforms have something other than 8-bit char?
...f you want an exact 8 bit type, use int8_t. Your code will noisily fail to compile on implementations which don't provide one, instead of silently using a size you didn't expect. At the very least, if I hit a case where I had a good reason to assume it, then I'd assert it.
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What does yield mean in PHP?
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What is a generator function?
A generator function is effectively a more compact and efficient way to write an Iterator. It allows you to define a function (your xrange) that will calculate and return values while you are looping over it:
foreach (xrange(1, 10) as $key => $value) {
echo "$...
Standard way to embed version into python package?
...ecifically? (Which "invents" your own double-underscore-word.) [When James commented, underscores did nothing in comments, now they indicate emphasis, so James really wrote __version_info__ too. ---ed.]
– Roger Pate
Dec 30 '09 at 1:32
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Python class inherits object
... for a class declaration to inherit from object?
In Python 3, apart from compatibility between Python 2 and 3, no reason. In Python 2, many reasons.
Python 2.x story:
In Python 2.x (from 2.2 onwards) there's two styles of classes depending on the presence or absence of object as a base-class:...
Generating random integer from a range
...ed non-uniform distributed numbers regardless the quality of rand(). For a comprehensive test of the quality of this method, please read this.
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