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What's the strangest corner case you've seen in C# or .NET? [closed]
... All the methods are overridden, except GetType() which can't be; so it is cast (boxed) to object (and hence to null) to call object.GetType()... which calls on null ;-p
Update: the plot thickens... Ayende Rahien threw down a similar challenge on his blog, but with a where T : class, new():
priv...
What is std::move(), and when should it be used?
...the object has type "rvalue-reference" (Type &&).
std::move() is a cast that produces an rvalue-reference to an object, to enable moving from it.
It's a new C++ way to avoid copies. For example, using a move constructor, a std::vector could just copy its internal pointer to data to the new...
convert an enum to another type of enum
...), value.ToString());
If you mean by numeric value, you can usually just cast:
Enum2 value2 = (Enum2)value;
(with the cast, you might want to use Enum.IsDefined to check for valid values, though)
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Using Linq to group a list of objects into a new grouped list of list of objects
...
var groupedCustomerList = userList
.GroupBy(u => u.GroupID)
.Select(grp => grp.ToList())
.ToList();
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How to get duration, as int milli's and float seconds from ?
... t1 = Time::now();
fsec fs = t1 - t0;
ms d = std::chrono::duration_cast<ms>(fs);
std::cout << fs.count() << "s\n";
std::cout << d.count() << "ms\n";
}
which for me prints out:
6.5e-08s
0ms
...
Throw an error in a MySQL trigger
... trigger_test values (1), (-1), (2); -- everything fails as one row is bad
select * from trigger_test;
insert into trigger_test values (1); -- succeeds as expected
insert into trigger_test values (-1); -- fails as expected
select * from trigger_test;
...
What would be C++ limitations compared C language? [closed]
..._t) );
To make it compile as C++ you have to write:
foo_t* foo = static_cast<foo_t*>( malloc ( sizeof(foo_t) ) );
which isn't valid C any more. (you could use the C-style cast, it which case it would compile in C, but be shunned by most C++ coding standards, and also by many C programmers...
How do I convert an object to an array?
...Single-dimensional arrays
For converting single-dimension arrays, you can cast using (array) or there's get_object_vars, which Benoit mentioned in
his answer.
// Cast to an array
$array = (array) $object;
// get_object_vars
$array = get_object_vars($object);
They work slightly different fro...
Method Overloading for null argument
... an explicit "null" (yet implicit null type) argument always unambiguously selects a specific overload ??
– peterk
Jul 18 '17 at 21:43
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Convert char to int in C and C++
... code, you can write
char a = 'a';
int ia = (int)a;
/* note that the int cast is not necessary -- int ia = a would suffice */
to convert the character '0' -> 0, '1' -> 1, etc, you can write
char a = '4';
int ia = a - '0';
/* check here if ia is bounded by 0 and 9 */
Explanation:
a - '0'...