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Why does ++[[]][+[]]+[+[]] return the string “10”?
This is valid and returns the string "10" in JavaScript ( more examples here ):
9 Answers
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What's the point of OOP?
...e of the countless millions or billions spent on OOP education, languages, and tools, OOP has not improved developer productivity or software reliability, nor has it reduced development costs. Few people use OOP in any rigorous sense (few people adhere to or understand principles such as LSP); there...
Access-Control-Allow-Origin wildcard subdomains, ports and protocols
I'm trying to enable CORS for all subdomains, ports and protocol.
11 Answers
11
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Java Security: Illegal key size or default parameters?
... had asked a question about this earlier, but it didn't get answered right and led nowhere.
19 Answers
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What's the difference between faking, mocking, and stubbing?
...t I'm wondering if there are accepted definitions for faking , mocking , and stubbing for unit tests? How do you define these for your tests? Describe situations where you might use each.
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How to compare two floating point numbers in Bash?
...) )); then
…
fi
Explanation
Piping through the basic calculator command bc returns either 1 or 0.
The option -l is equivalent to --mathlib; it loads the standard math library.
Enclosing the whole expression between double parenthesis (( )) will translate these values to respectively true or...
Which SQL query is faster? Filter on Join criteria or Where clause?
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Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
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Confusion between factor levels and factor labels
There seems to be a difference between levels and labels of a factor in R.
Up to now, I always thought that levels were the 'real' name of factor levels, and labels were the names used for output (such as tables and plots). Obviously, this is not the case, as the following example shows:
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Get image data url in JavaScript?
... the same domain as the page, or has the crossOrigin="anonymous" attribute and the server supports CORS. It's also not going to give you the original file, but a re-encoded version. If you need the result to be identical to the original, see Kaiido's answer.
You will need to create a canvas eleme...
Why should I use a pointer rather than the object itself?
I'm coming from a Java background and have started working with objects in C++. But one thing that occurred to me is that people often use pointers to objects rather than the objects themselves, for example this declaration:
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