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Why is there “data” and “newtype” in Haskell? [duplicate]
It seems that a newtype definition is just a data definition that obeys some restrictions (e.g., only one constructor), and that due to these restrictions the runtime system can handle newtype s more efficiently. And the handling of pattern matching for undefined values is slightly different.
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Is there any overhead to declaring a variable within a loop? (C++)
...laring a variable inside a loop and I was wondering what's wrong until he cited performance as the reason not to do so and I was like "WTF!?".
– Mehrdad Afshari
Jun 11 '09 at 19:35
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How to add elements to an empty array in PHP?
If I define an array in PHP such as (I don't define its size):
8 Answers
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Programmatically get own phone number in iOS
...K Agreement as of Nov 5, 2009. Our application was just rejected for using it. Here's the response from Apple:
"For security reasons, iPhone OS restricts an application (including its preferences and data) to a unique location in the file system. This restriction is part of the security feature kno...
What is the difference between bottom-up and top-down?
...r answers said that "bottom-up is memoization" ("assume the subproblems"), it may be the inverse (that is, "top-down" may be "assume the subproblems" and "bottom-up" may be "compose the subproblems"). Previously, I have read on memoization being a different kind of dynamic programming as opposed to ...
Why is “throws Exception” necessary when calling a function?
...o specify a throws clause for all classes. Specifically, classes that are either an Error or RuntimeException or any of the subclasses of these two. In your case Exception is not a subclass of an Error or RuntimeException. So, it is a checked exception and must be specified in the throws clause, if ...
Is it possible to make the -init method private in Objective-C?
I need to hide (make private) the -init method of my class in Objective-C.
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Check if object is file-like in Python
...objects in Python that behave like a real file, e.g. have a read() and a write method(), but have a different implementation. It is and realization of the Duck Typing concept.
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Collection versus List what should you use on your interfaces?
...s to why not List<T>, The reasons are future-proofing and API simplicity.
Future-proofing
List<T> is not designed to be easily extensible by subclassing it; it is designed to be fast for internal implementations. You'll notice the methods on it are not virtual and so cannot be overridd...
Where is the C auto keyword used?
... about the auto keyword and in the course of time I actually forgot what it is. It is defined as:
9 Answers
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