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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 (...) {
// .....
Why does my application spend 24% of its life doing a null check?
I've got a performance critical binary decision tree, and I'd like to focus this question on a single line of code. The code for the binary tree iterator is below with the results from running performance analysis against it.
...
Different results with Java's digest versus external utilities
... I am using Windows 7 Professional with SP1 . I have tried Java 6.0.29 and Java 7.0.03 . Can someone tell me why I am getting different hash values from Java versus (many!) external utilities and/or websites? Everything external matches with each other, only Java is returning different result...
What's the difference between Invoke() and BeginInvoke()
Just wondering what the difference between BeginInvoke() and Invoke() are?
6 Answers
...
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...
What does iterator->second mean?
...const X, Y>s. That's exactly what a map is - it pairs together the keys and the associated values.
When you iterate over a std::map, you're iterating over all of these std::pairs. When you dereference one of these iterators, you get a std::pair containing the key and its associated value.
std::...
Best way to store time (hh:mm) in a database
I want to store times in a database table but only need to store the hours and minutes.
I know I could just use DATETIME and ignore the other components of the date, but what's the best way to do this without storing more info than I actually need?
...
How exactly does __attribute__((constructor)) work?
...nguish them from function calls.
GCC-specific syntax.
Yes, this works in C and C++.
No, the function does not need to be static.
The destructor runs when the shared library is unloaded, typically at program exit.
So, the way the constructors and destructors work is that the shared object file cont...
How to execute a Python script from the Django shell?
...
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...
Merge two Git repositories without breaking file history
I need to merge two Git repositories into a brand new, third repository. I've found many descriptions of how to do this using a subtree merge (for example Jakub Narębski's answer on How do you merge two Git repositories? ) and following those instructions mostly works, except that when I commit...