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Why doesn't c++ have &&= or ||= for booleans?
... as both operands are of type bool.1
Contrary to what other people have said here, a bool in C++ must never have a different value such as 2. When assigning that value to a bool, it will be converted to true as per the standard.
The only way to get an invalid value into a bool is by using reinterp...
Why should I prefer single 'await Task.WhenAll' over multiple awaits?
...conserving the same SynchronizationContext, to further push its benefits aside from the semantics. I found no conclusive documentation, but looking at the IL there are evidently different implementations of IAsyncStateMachine in play. I don't read IL all that well, but WhenAll at the very least appe...
How to throw a C++ exception
...int a, int b ) {
if ( a < 0 || b < 0 ) {
throw std::invalid_argument( "received negative value" );
}
}
The Standard Library comes with a nice collection of built-in exception objects you can throw. Keep in mind that you should always throw by value and catch by reference:
t...
Haskell: Lists, Arrays, Vectors, Sequences
...
work wonderfully. Infinite data structures rock.
Lists in Haskell provide an interface much like iterators in imperative languages (because of laziness). So, it makes sense that they are widely used.
On the other hand
The first problem with lists is that to index into them (!!) takes ϴ(k)...
How to get a reference to current module's attributes in Python
... symbol
table. This is always the dictionary
of the current module (inside a
function or method, this is the module
where it is defined, not the module
from which it is called).
http://docs.python.org/library/functions.html#globals
...
I want to get the type of a variable at runtime
...[T: Manifest](t: T): Manifest[T] = manifest[T]
manOf: [T](t: T)(implicit evidence$1: Manifest[T])Manifest[T]
scala> val x = List(1,2,3)
x: List[Int] = List(1, 2, 3)
scala> println(manOf(x))
scala.collection.immutable.List[Int]
If you are in repl mode then
scala> :type List(1,2,3)
List...
In Visual Studio C++, what are the memory allocation representations?
...
We used to use C0CAC01A when we did some low-level (operating system kernel) programming back in the days... ;)
– Per Lundberg
Sep 4 '13 at 12:36
...
MPICH vs OpenMPI
...ports both of these networks and others natively (i.e. without OFI in the middle).
In the past, a common complaint about MPICH is that it does not support InfiniBand, whereas Open-MPI does. However, MVAPICH and Intel MPI (among others) - both of which are MPICH derivatives - support InfiniBand, so...
Generic method multiple (OR) type constraint
...ossible. You can, however, define overloads for specific types:
public void test(string a, string arg);
public void test(string a, Exception arg);
If those are part of a generic class, they will be preferred over the generic version of the method.
...
Most efficient way of making an if-elif-elif-else statement when the else is done the most?
...ion, which can be a significant performance overhead in a tight loop.
Consider these examples...
1.py
something = 'something'
for i in xrange(1000000):
if something == 'this':
the_thing = 1
elif something == 'that':
the_thing = 2
elif something == 'there':
the...