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Finding the type of an object in C++
...
dynamic_cast should do the trick
TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime...
Case objects vs Enumerations in Scala
...nswered Dec 14 '09 at 9:27
oxbow_lakesoxbow_lakes
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std::unique_lock or std::lock_guard?
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The difference is that you can lock and unlock a std::unique_lock. std::lock_guard will be locked only once on construction and unlocked on destruction.
So for use case B you definitely need a std::unique_lock for the condition variable. In case A it depends whether you need to relo...
Insert, on duplicate update in PostgreSQL?
...FLICT clause. with the following syntax (similar to MySQL)
INSERT INTO the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group a...
How to verify that method was NOT called in Moq?
...
Run a verify after the test which has a Times.Never enum set. e.g.
_mock.Object.DoSomething()
_mock.Verify(service => service.ShouldntBeCalled(), Times.Never);
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Get all attributes of an element using jQuery
...core
Also works for lodash.
function getAttributes ( node ) {
return _.reduce( node.attributes, function ( attrs, attribute ) {
attrs[attribute.name] = attribute.value;
return attrs;
}, {} );
}
lodash
Is even more concise than the Underscore version, but only works for l...
What are rvalues, lvalues, xvalues, glvalues, and prvalues?
... three: lvalue, xvalue, prvalue. A Venn diagram would look like this:
______ ______
/ X \
/ / \ \
| l | x | pr |
\ \ / /
\______X______/
gl r
Examples with functions:
int prvalue();
int& lvalue();
int&& xvalue();
But al...
How to call Stored Procedure in Entity Framework 6 (Code-First)?
...bContext as your own instances:
public void addmessage(<yourEntity> _msg)
{
var date = new SqlParameter("@date", _msg.MDate);
var subject = new SqlParameter("@subject", _msg.MSubject);
var body = new SqlParameter("@body", _msg.MBody);
var fid = new SqlParameter("@fid", _msg.FI...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
... should remember that it is not C# source that executes but rather IL:
IL_0001: ldnull
IL_0002: stloc.0 // s
IL_0003: ldloc.0 // s
IL_0004: callvirt System.String.get_Length
IL_0009: call System.Console.WriteLine
It is the callvirt opcode that throws the NullReferenc...
Is there a short contains function for lists?
..., you may also be interested to know that what in does is to call the list.__contains__ method, that you can define on any class you write and can get extremely handy to use python at his full extent.
A dumb use may be:
>>> class ContainsEverything:
def __init__(self):
retu...