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Is there a difference between foreach and map?
Ok this is more of a computer science question, than a question based on a particular language, but is there a difference between a map operation and a foreach operation? Or are they simply different names for the same thing?
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Where am I? - Get country
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This will get the country code set for the phone (phones language, NOT user location):
String locale = context.getResources().getConfiguration().locale.getCountry();
can also replace getCountry() with getISO3Country() to get a 3 letter ISO code for the cou...
Get the index of the object inside an array, matching a condition
... of 2016, you're supposed to use Array.findIndex (an ES2015/ES6 standard) for this:
a = [
{prop1:"abc",prop2:"qwe"},
{prop1:"bnmb",prop2:"yutu"},
{prop1:"zxvz",prop2:"qwrq"}];
index = a.findIndex(x => x.prop2 ==="yutu");
console.log(index);
It's supported in Google ...
Copy file or directories recursively in Python
Python seems to have functions for copying files (e.g. shutil.copy ) and functions for copying directories (e.g. shutil.copytree ) but I haven't found any function that handles both. Sure, it's trivial to check whether you want to copy a file or a directory, but it seems like a strange omission.
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What are the differences between “=” and “
What are the differences between the assignment operators = and <- in R?
7 Answers
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Volatile Vs Atomic [duplicate]
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The effect of the volatile keyword is approximately that each individual read or write operation on that variable is atomic.
Notably, however, an operation that requires more than one read/write -- such as i++, which is equivalent to i = i + 1, which does...
Nested or Inner Class in PHP
I'm building a User Class for my new website, however this time I was thinking to build it little bit differently...
10 A...
WARN Could not determine content-length of response body. Set content-length of the response or set
...upgraded to rails 3.2.2, and now on rails s, page load, I get all these errors in the log:
3 Answers
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Is it possible to determine whether ViewController is presented as Modal?
...e modalViewController has been deprecated in iOS 6, here's a version that works for iOS 5+ and that compiles without warnings.
Objective-C:
- (BOOL)isModal {
return self.presentingViewController.presentedViewController == self
|| (self.navigationController != nil && self.navigati...
How to check if a Ruby object is a Boolean
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Yes, that's called duck typing and a core principle of OOP. I think it's a feature.
– Konstantin Haase
Jun 19 '12 at 16:41
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