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What are enums and why are they useful?
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You should always use enums when a variable (especially a method parameter) can only take one out of a small set of possible values. Examples would be things like type constants (contract status: "permanent", "temp", "apprentice"), or flags ("execute now", "defer execution")....
How to loop through array in jQuery?
... of this within the body of the loop, no unnecessary overhead of function calls (e.g., in theory faster, though in fact you'd have to have so many elements that the odds are you'd have other problems; details).
ES5's forEach:
As of ECMAScript5, arrays have a forEach function on them which makes it...
How do you use “git --bare init” repository?
...ush) from another repository.
Note that in this case you'll need to first allow people to push to your repository. When inside test_repo.git, do
git config receive.denyCurrentBranch ignore
Community edit
git init --bare --shared=group
As commented by prasanthv, this is what you want if you ar...
T-SQL stored procedure that accepts multiple Id values
...sing the List as Many Parameters. Tedious and error prone, but simple.
Really Slow Methods. Methods that uses charindex, patindex or LIKE.
I really can't recommend enough to read the article to learn about the tradeoffs among all these options.
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What is the best testing framework to use with Node.js? [closed]
...TJ Holowaychuk who is also the creator of Express.js (insanely fast (and small) server-side JavaScript web development framework built on Node.js and Connect). I recently saw that he also has a cool library called should.js which can be used together with Expresso for a even better testing experienc...
Why does direction of index matter in MongoDB?
...d query in the same order as the index will simply return the rows sequentially in the correct order.
Finding a record in a BTree takes O(Log(n)) time. Finding a range of records in order is only OLog(n) + k where k is the number of records to return.
If the records are out of order, the cost coul...
Are the shift operators () arithmetic or logical in C?
...ependent for right shifts of signed values.
Wikipedia says that C/C++ 'usually' implements an arithmetic shift on signed values.
Basically you need to either test your compiler or not rely on it. My VS2008 help for the current MS C++ compiler says that their compiler does an arithmetic shift.
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C++ Tuple vs Struct
... not the purpose of this discussion so I won't dive into the detail.
We all know that writing a == or < or > operator for every single struct definition will be a painful and buggy task. Let replace our custom comparator using std::tie and rerun our benchmark.
bool operator<(const Str...
Finding all possible permutations of a given string in python
I have a string. I want to generate all permutations from that string, by changing the order of characters in it. For example, say:
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How to reorder data.table columns (without copying)
... 2 2
# [3,] 0.3297416 1 3
From ?setcolorder:
In data.table parlance, all set* functions change their input by reference. That is, no copy is made at all, other than temporary working memory, which is as large as one column.
so should be pretty efficient. See ?setcolorder for details.
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