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How to check if a file exists in Go?
...or not (like Python's os.path.exists ). What is the idiomatic way to do it?
11 Answers
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Is the C# static constructor thread safe?
...cts/static-constructors
The implementation shown is thread safe for the initial construction, that is, no locking or null testing is required for constructing the Singleton object. However, this does not mean that any use of the instance will be synchronised. There are a variety of ways that this c...
PHP: If internet explorer 6, 7, 8 , or 9
I want to do a conditional in PHP for the different versions of Internet Explorer along the lines of:
17 Answers
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Which is faster: while(1) or while(2)?
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Both loops are infinite, but we can see which one takes more instructions/resources per iteration.
Using gcc, I compiled the two following programs to assembly at varying levels of optimization:
int main(void) {
while(1) {}
return 0;
}
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Positioning MKMapView to show multiple annotations at once
I've got several annotations I want to add to my MKMapView (it could 0-n items, where n is generally around 5). I can add the annotations fine, but I want to resize the map to fit all annotations onscreen at once, and I'm not sure how to do this.
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Does JavaScript have a method like “range()” to generate a range within the supplied bounds?
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Numbers
[...Array(5).keys()];
=> [0, 1, 2, 3, 4]
Character iteration
String.fromCharCode(...[...Array('D'.charCodeAt(0) - 'A'.charCodeAt(0) + 1).keys()].map(i => i + 'A'.charCodeAt(0)));
=> "ABCD"
Iteration
for (const x of Array(5).keys()) {
console.log(x, String.fromCha...
Get a random boolean in python?
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Adam's answer is quite fast, but I found that random.getrandbits(1) to be quite a lot faster. If you really want a boolean instead of a long then
bool(random.getrandbits(1))
is still about twice as fast as random.choice([True, False])
Both ...
What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?
I am transitioning from Java to C++ and have some questions about the long data type. In Java, to hold an integer greater than 2 32 , you would simply write long x; . However, in C++, it seems that long is both a data type and a modifier.
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Disable Visual Studio code formatting in Razor
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Actually it's worse in 2015 than the 2013 version (the same apply to C# where it will indent unrelated things each time you open a brace). I used to love visual studio but this is slowly killing it.
– youen
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Iterating over Java collections in Scala
I'm writing some Scala code which uses the Apache POI API. I would like to iterate over the rows contained in the java.util.Iterator that I get from the Sheet class. I would like to use the iterator in a for each style loop, so I have been trying to convert it to a native Scala collection but ...