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Unable to Cast from Parent Class to Child Class

... A simple way to downcast in C# is to serialize the parent and then deserialize it into the child. var serializedParent = JsonConvert.SerializeObject(parentInstance); Child c = JsonConvert.DeserializeObject<Child>(serializedParent); I have a simple console app that casts...
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Securing my REST API with OAuth while still allowing authentication via third party OAuth providers

... First I'd like to emphasize the difference between authentication and authorization: A user authenticates to your web site by supplying some credential such as a username+password. OpenID allows this to be displaced by having the user authenticate to another service, which then asserts th...
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Retain precision with double in Java

...of 11.4. Now, a little explanation into why this is happening: The float and double primitive types in Java are floating point numbers, where the number is stored as a binary representation of a fraction and a exponent. More specifically, a double-precision floating point value such as the double...
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How to launch Safari and open URL from iOS app

... But this is not 100%, because if someone use a jailbreaked iOS and use Chrome or something as default browser, then this will open that, not Safari – Laszlo Sep 30 '13 at 12:55 ...
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How can I capitalize the first letter of each word in a string?

...ition works in many contexts but it means that apostrophes in contractions and possessives form word boundaries, which may not be the desired result: >>> "they're bill's friends from the UK".title() "They'Re Bill'S Friends From The Uk" ...
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How do you rename a MongoDB database?

There's a typo in my MongoDB database name and I'm looking to rename the database. 10 Answers ...
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How is this fibonacci-function memoized?

...mechanism in Haskell is by-need: when a value is needed, it is calculated, and kept ready in case it is asked for again. If we define some list, xs=[0..] and later ask for its 100th element, xs!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for next access. Th...
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Does assignment with a comma work?

Why does aaa = 1,2,3 work and set the value of aaa to 1 ? 4 Answers 4 ...
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Are 2^n and n*2^n in the same time complexity?

... answer this question. The definition is that f(x) belongs to O(g(x)) if and only if the limit limsupx → ∞ (f(x)/g(x)) exists i.e. is not infinity. In short this means that there exists a constant M, such that value of f(x)/g(x) is never greater than M. In the case of your question let f(n) ...
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Checking for a dirty index or untracked files with Git

...;/dev/null| grep "^M" | wc -l) # Get number of files that are uncommitted and not added expr $(git status --porcelain 2>/dev/null| grep "^ M" | wc -l) # Get number of total uncommited files expr $(git status --porcelain 2>/dev/null| egrep "^(M| M)" | wc -l) Note: The 2>/dev/null filters...