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How do JavaScript closures work?
How would you explain JavaScript closures to someone with a knowledge of the concepts they consist of (for example functions, variables and the like), but does not understand closures themselves?
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Why do you need ./ (dot-slash) before executable or script name to run it in bash?
When running scripts in bash, I have to write ./ in the beginning:
9 Answers
9
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Difference between 'new operator' and 'operator new'?
...ually try to phrase things differently to differentiate between the two a bit better, but it's a good question in any case.
Operator new is a function that allocates raw memory -- at least conceptually, it's not much different from malloc(). Though it's fairly unusual unless you're writing somethin...
structure vs class in swift language
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Here's an example with a class. Note how when the name is changed, the instance referenced by both variables is updated. Bob is now Sue, everywhere that Bob was ever referenced.
class SomeClass {
var name: String
init(name: String) {
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Cannot delete directory with Directory.Delete(path, true)
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Editor's note: Although this answer contains some useful information, it is factually incorrect about the workings of Directory.Delete. Please read the comments for this answer, and other answers to this question.
I ran into...
How can I ensure that a division of integers is always rounded up?
... blog in January 2013. Thanks for the great question!
Getting integer arithmetic correct is hard. As has been demonstrated amply thus far, the moment you try to do a "clever" trick, odds are good that you've made a mistake. And when a flaw is found, changing the code to fix the flaw without cons...
ValidateRequest=“false” doesn't work in Asp.Net 4
I have a form at which I use ckeditor. This form worked fine at Asp.Net 2.0 and 3.5 but now it doesn't work in Asp.Net 4+. I have ValidateRequest="false" directive. Any suggestions?
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How to add an integer to each element in a list?
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This talk explains it: Facts and Myths about Python Names and Values: nedbatchelder.com/text/names1.html
– Ned Batchelder
Dec 2 '16 at 13:36
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What's a concise way to check that environment variables are set in a Unix shell script?
..."}
: ${DEST:?"Need to set DEST non-empty"}
Or, better (see section on 'Position of double quotes' below):
: "${STATE?Need to set STATE}"
: "${DEST:?Need to set DEST non-empty}"
The first variant (using just ?) requires STATE to be set, but STATE="" (an empty string) is OK — not exactly what you ...
Test if a variable is a list or tuple
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Go ahead and use isinstance if you need it. It is somewhat evil, as it excludes custom sequences, iterators, and other things that you might actually need. However, sometimes you need to behave differently if someone, for instance, passes a string. My preference...