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Resolve build errors due to circular dependency amongst classes

...ember that the .cc and not the .h is the unit of compilation), you need to allocate space for object A. So, well, how much space then? Enough to store B! What's the size of B then? Enough to store A! Oops. Clearly a circular reference that you must break. You can break it by allowing the compiler ...
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How does deriving work in Haskell?

Algebraic Data Types (ADTs) in Haskell can automatically become instances of some typeclasse s (like Show , Eq ) by deriving from them. ...
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How to calculate the difference between two dates using PHP?

...ferred way of doing this is like described by jurka below. My code is generally only recommended if you don't have PHP 5.3 or better. Several people in the comments have pointed out that the code above is only an approximation. I still believe that for most purposes that's fine, since the usage of...
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In what areas might the use of F# be more appropriate than C#? [closed]

... sweet spot for the language within enterprise software, namely algorithmically complex analysis of large data sets. My experience has been a very positive one. In particular: Units of measure The industry I work in is littered with units. The equations I implemented (often of a geometric nature) d...
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Python, creating objects

... = "" age = 0 major = "" # The class "constructor" - It's actually an initializer def __init__(self, name, age, major): self.name = name self.age = age self.major = major def make_student(name, age, major): student = Student(name, age, major) return...
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Why doesn't Python have a sign function?

... it wasn't accepted, because they didn't agree on what it should return in all the edge cases (+/-0, +/-nan, etc) So they decided to implement only copysign, which (although more verbose) can be used to delegate to the end user the desired behavior for edge cases - which sometimes might require the...
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Stop pip from failing on single package when installing with requirements.txt

I am installing packages from requirements.txt 6 Answers 6 ...
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How do I get list of methods in a Python class?

... Will this produce a list of all methods in the class (including ones that are inherited from other classes), or will it only list the methods that are explicitly defined in that class? – Anderson Green Mar 10 '13 a...
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Remove duplicate elements from array in Ruby

... array = array.uniq uniq removes all duplicate elements and retains all unique elements in the array. This is one of many beauties of the Ruby language. share | ...
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What is your favorite C programming trick? [closed]

... C99 offers some really cool stuff using anonymous arrays: Removing pointless variables { int yes=1; setsockopt(yourSocket, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)); } becomes setsockopt(yourSocket, SOL_SOCKET, SO_REUSEADDR...