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What is an optional value in Swift?
...g and writing code more fluent. Unfortunately this obscures the way it actually works. I'll go through some of the tricks later.
Note: I'll be talking about optional variables a lot, but it's fine to create optional constants too. I mark all variables with their type to make it easier to understand ...
What's the optimum way of storing an NSDate in NSUserDefaults?
...directly and watch it Do The Right Thing (including time zones, precision, etc). There is no formatter involved, as others have said.
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How can I get sin, cos, and tan to use degrees instead of radians?
... radians to degrees
* @param {function} trigFunc - eg. Math.cos, Math.sin, etc.
* @param {number} angle - in degrees
* @returns {number}
*/
const dTrig = (trigFunc, angle) => trigFunc(angle * Math.PI / 180);
or,
function dTrig(trigFunc, angle) {
return trigFunc(angle * Math.PI / 180);
}
wh...
Is the order of iterating through std::map known (and guaranteed by the standard)?
...
Yes, that's guaranteed. Moreover, *begin() gives you the smallest and *rbegin() the largest element, as determined by the comparison operator, and two key values a and b for which the expression !compare(a,b) && !compare(b,a) is true are considered equal. The default comparis...
How to get error message when ifstream open fails
...
Every system call that fails update the errno value.
Thus, you can have more information about what happens when a ifstream open fails by using something like :
cerr << "Error: " << strerror(errno);
However, since every s...
What is a servicebus and when do I need one?
...tion between different services, different versions of different services, etc. (including situations where the services use different protocols).
– Justin Niessner
Apr 27 '10 at 22:01
...
Differences between numpy.random and random.random in Python
...of much higher quality than is available from random.random alone. You usually don't need this, though.
– SingleNegationElimination
Aug 11 '11 at 18:36
...
How to return multiple objects from a Java method?
... if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
@SuppressWarnings("rawtypes")
Pair other = (Pair) obj;
if (a == null) {
if (other.a != null) {
return fals...
Why is it faster to check if dictionary contains the key, rather than catch the exception in case it
...ng exceptions is inherently expensive, because the stack has to be unwound etc.
On the other hand, accessing a value in a dictionary by its key is cheap, because it's a fast, O(1) operation.
BTW: The correct way to do this is to use TryGetValue
obj item;
if(!dict.TryGetValue(name, out item))
r...
A top-like utility for monitoring CUDA activity on a GPU
...o worked for me on redhat 8 when I was getting some error due to importing _curses in python.
– Bobak Hashemi
Aug 6 '19 at 22:32
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