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Safe (bounds-checked) array lookup in Swift, through optional bindings?
..., to clarify the situation: b contains a value and the value is nil. If we casted automatically to Int?, we would loose the information, if we got a hit or a miss in the array, which might be necessary in some circumstances. I would rather debate, if Swift could get rid of automatically casting valu...
What's the correct way to communicate between controllers in AngularJS?
...essed in this answer have been resolved in angular.js version 1.2.7. $broadcast now avoids bubbling over unregistered scopes and runs just as fast as $emit.
So, now you can:
use $broadcast from the $rootScope
listen using $on from the local $scope that needs to know about the event
Original ...
Implicit type conversion rules in C++ operators
I want to be better about knowing when I should cast. What are the implicit type conversion rules in C++ when adding, multiplying, etc. For example,
...
How do I check if a type is a subtype OR the type of an object?
...lue);
if (testInstance==null)
throw new InvalidCastException("HelperType must be derived from A");
_helperType = value;
}
}
}
I feel like I might be a bit naive here so any feedback would be welcome.
...
How do I pass a unique_ptr argument to a constructor or a function?
...eter by value. std::move doesn't actually move anything; it's just a fancy cast. std::move(nextBase) returns a Base&& that is an r-value reference to nextBase. That's all it does.
Because Base::Base(std::unique_ptr<Base> n) takes its argument by value rather than by r-value reference,...
C++ preprocessor __VA_ARGS__ number of arguments
...
@Adam Because I cast {__VA_ARGS__} to int[], it is just int[], regardless of actual content of __VA_ARGS__
– qrdl
Jan 23 '10 at 20:45
...
Adding two Java 8 streams, or an extra element to a stream
...type of Something<? extends T>, not the other way, so it couldn't be cast) Additional .map(identity()) cast <? extends T> to <T>. It happens thanks to mix of java 8 'target types' of method arguments and return types and signature of map() method. Actually it is Function.<T>i...
What is a difference between
...ecause you can be sure that whatever the actual list contains, it can be upcasted to a Number (after all anything that extends Number is a Number, right?)
However, you are not allowed to put anything into a covariant structure.
myNumst.add(45L); //compiler error
This would not be allowed, because J...
Measuring execution time of a function in C++
...::high_resolution_clock::now();
auto duration = std::chrono::duration_cast<std::chrono::microseconds>( t2 - t1 ).count();
std::cout << duration;
return 0;
}
This will measure the duration of the function.
NOTE: You will not always get the same timing for a function. This...
How do I reflect over the members of dynamic object?
...lt;string, object> for its properties, so the solution is as trivial as casting:
IDictionary<string, object> propertyValues = (IDictionary<string, object>)s;
Note that this will not work for general dynamic objects. In these cases you will need to drop down to the DLR via IDynamic...