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Python unittest - opposite of assertRaises?
I want to write a test to establish that an Exception is not raised in a given circumstance.
10 Answers
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ReactJS - Does render get called any time “setState” is called?
...te(object nextProps, object nextState), each component has this method and it's responsible to determine "should component update (run render function)?" every time you change state or pass new props from parent component.
You can write your own implementation of shouldComponentUpdate method for yo...
Javascript reduce on array of objects
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After the first iteration your're returning a number and then trying to get property x of it to add to the next object which is undefined and maths involving undefined results in NaN.
try returning an object contain an x property with the ...
Unique (non-repeating) random numbers in O(1)?
...t doesn't resort to something like an O(N) search of previous values to do it. Is this possible?
22 Answers
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select * vs select column
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It always pulls a tuple (except in cases where the table has been vertically segmented - broken up into columns pieces), so, to answer the question you asked, it doesn't matter from a performance perspective. However, for ma...
vs
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In HTML5, they are equivalent. Use the shorter one, it is easier to remember and type. Browser support is fine since it was designed for backwards compatibility.
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C++ catching all exceptions
... // ...
} catch (...) {
// ...
}
will catch all C++ exceptions, but it should be considered bad design. You can use c++11's new current_exception mechanism, but if you don't have the ability to use c++11 (legacy code systems requiring a rewrite), then you have no named exception pointer to u...
Xcode 6 iPhone Simulator Application Support location
...upport for the iOS 8 iPhone Simulator. Where are my files and Core Data sqlite database being stored?
16 Answers
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How does a “stack overflow” occur and how do you prevent it?
How does a stack overflow occur and what are the best ways to make sure it doesn't happen, or ways to prevent one, particularly on web servers, but other examples would be interesting as well?
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How to sort a dataframe by multiple column(s)
I want to sort a data.frame by multiple columns. For example, with the data.frame below I would like to sort by column z (descending) then by column b (ascending):
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