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How to return an empty ActiveRecord relation?
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There is a now a "correct" mechanism in Rails 4:
>> Model.none
=> #<ActiveRecord::Relation []>
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Could not load file or assembly or one of its dependencies
I'm having another of these "Could not load file or assembly or one of its dependencies" problems.
43 Answers
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What is a None value?
I have been studying Python, and I read a chapter which describes the None value, but unfortunately this book isn't very clear at some points. I thought that I would find the answer to my question, if I share it there.
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Sort points in clockwise order?
...lgorithm you like, but use special comparison routine to determine whether one point is less than the other.
You can check whether one point (a) is to the left or to the right of the other (b) in relation to the center by this simple calculation:
det = (a.x - center.x) * (b.y - center.y) - (b.x - ...
Why use ICollection and not IEnumerable or List on many-many/one-many relationships?
...exts, that type will yield slightly better performance than would a standalone heap object. Compilers which duck-type enumerators (as both C# and vb.net do) can take advantage of this when generating foreach code. If the List<T> is cast to IEnumrable<T> before the foreach, the IEnumera...
Class method differences in Python: bound, unbound and static
...and unbound methods.
Basically, a call to a member function (like method_one), a bound function
a_test.method_one()
is translated to
Test.method_one(a_test)
i.e. a call to an unbound method. Because of that, a call to your version of method_two will fail with a TypeError
>>> a_test...
Calculate the median of a billion numbers
If you have one billion numbers and one hundred computers, what is the best way to locate the median of these numbers?
25 A...
Algorithm to return all combinations of k elements from n
.... Let's say {1,2,3} we can say that the difference between the elements is one and in order and minimal. {1,2,4} has one change and is lexicographically number 2. So the number of 'changes' in the last place accounts for one change in the lexicographical ordering. The second place, with one change {...
How to “properly” print a list?
...element of mylist, creating a new list of strings that is then joined into one string with str.join(). Then, the % string formatting operator substitutes the string in instead of %s in "[%s]".
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How to change time and timezone in iPhone simulator?
How do I change time and time zone in the iPhone simulator?
11 Answers
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