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Why do we not have a virtual constructor in C++?
...
Hear it from the horse's mouth. :)
From Bjarne Stroustrup's C++ Style and Technique FAQ Why don't we have virtual constructors?
A virtual call is a mechanism to get work done given partial
information. In particular, "virtual" allows us to call a function
knowing only any interfaces and...
C++ catching all exceptions
...nt to add separate catch clauses for the various exceptions you can catch, and only catch everything at the bottom to record an unexpected exception. E.g.:
try{
// ...
} catch (const std::exception& ex) {
// ...
} catch (const std::string& ex) {
// ...
} catch (...) {
// .....
Extension method and dynamic object
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To expand on Stecya's answer... extension methods aren't supported by dynamic typing in the form of extension methods, i.e. called as if they were instance methods. However, this will work:
dynamic dList = list;
Console.WriteLine(...
spring boot default H2 jdbc connection (and H2 console)
...ng-boot creates when I don't specify anything in my application.properties and start with mvn spring:run. I can see hibernate JPA creating the tables but if I try to access the h2 console at the URL below the database has no tables.
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Best way to test for a variable's existence in PHP; isset() is clearly broken
...l scope variables as well, on can do a $defined_vars = get_defined_vars(); and then test via array_key_exists('v', $defined_vars);.
– Henrik Opel
Sep 27 '10 at 16:01
1
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Is effective C++ still effective?
...t on his own blog
Which may lead you to wonder whether the information and advice in
this pre-C++0x edition of Effective C++ remains relevant. I'm pleased
to report that it does. Surprisingly so, in fact. Having spent nearly
two years steeped in the details of C++0x, I expected to groan a ...
Fastest Way of Inserting in Entity Framework
... for example 100 records.
Call SaveChanges() after for example 100 records and dispose the context and create a new one.
Disable change detection
For bulk inserts I am working and experimenting with a pattern like this:
using (TransactionScope scope = new TransactionScope())
{
MyDbContext con...
Which HTML5 reset CSS do you use and why? [closed]
Which HTML5 reset CSS do you use and why? Is there one that you've found to cover more cases?
8 Answers
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How to execute a Python script from the Django shell?
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Another solution that appears to work for both Python 2.x and 3.x is echo 'import myscript' | python manage.py shell. I've found this can be useful for quick-and-dirty scripts that you only need to run once, without having to go through the cumbersome process of creating a manage.py...
Remove all child elements of a DOM node in JavaScript
... will be faster than innerHTML as browsers won't invoke their HTML parsers and will instead immediately replace all children of the element with a single #text node.
doFoo.onclick = () => {
const myNode = document.getElementById("foo");
myNode.textContent = '';
}
<div id='foo' st...