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Convert tuple to list and back
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@Jimmy that's because list is a debugger command, run p list(...) instead.
– moritz
Jan 24 '19 at 2:26
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JavaScript checking for null vs. undefined and difference between == and ===
...hey're falsey:
if (!a) {
// `a` is falsey, which includes `undefined` and `null`
// (and `""`, and `0`, and `NaN`, and [of course] `false`)
}
This is defined by ToBoolean in the spec.
...and what is the difference between the null and undefined?
They're both values usually used to i...
How do I declare and initialize an array in Java?
How do I declare and initialize an array in Java?
28 Answers
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How can I match a string with a regex in Bash?
...is not a concern, I recommend using [[ instead of [ or test as it is safer and more powerful. See What is the difference between test, [ and [[ ? for details.
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Unicode equivalents for \w and \b in Java regular expressions?
Many modern regex implementations interpret the \w character class shorthand as "any letter, digit, or connecting punctuation" (usually: underscore). That way, a regex like \w+ matches words like hello , élève , GOÄ_432 or gefräßig .
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Comparing numbers in Bash
...hen
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fi
For POSIX shells that don't support (()), you can use -lt and -gt.
if [ "$a" -gt "$b" ]; then
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fi
You can get a full list of comparison operators with help test or man test.
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Javascript and regex: split string and keep the separator
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I don't understand why everybody is using /g
– Sarsaparilla
Jan 11 '17 at 18:22
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Git for beginners: The definitive practical guide
...k, after seeing this post by PJ Hyett , I have decided to skip to the end and go with Git .
37 Answers
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OpenCV C++/Obj-C: Detecting a sheet of paper / Square Detection
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This is a recurring subject in Stackoverflow and since I was unable to find a relevant implementation I decided to accept the challenge.
I made some modifications to the squares demo present in OpenCV and the resulting C++ code below is able to detect a sheet of paper ...
Is R's apply family more than syntactic sugar?
...regarding execution time and / or memory.
5 Answers
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