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How to do constructor chaining in C#
I know that this is supposedly a super simple question, but I've been struggling with the concept for some time now.
8 An...
How to profile a bash shell script slow startup?
...2 2> >(tee /tmp/sample-time.$$.log |
sed -u 's/^.*$/now/' |
date -f - +%s.%N >/tmp/sample-time.$$.tim)
set -x
Doing this will run date only once. There is a quick demo/test to show how it work:
for i in {1..4};do echo now;sleep .05;done| date -f - +%N
...
Else clause on Python while statement
...struct:
while condition:
handle_true()
else:
# condition is false now, handle and go on with the rest of the program
handle_false()
An example might be along the lines of:
while value < threshold:
if not process_acceptable_value(value):
# something went wrong, exit the...
C++ equivalent of java's instanceof
...seClass>(ptr)) { ... }
However, this purely operates on the types as known by the compiler.
Edit:
This code should work for polymorphic pointers:
template<typename Base, typename T>
inline bool instanceof(const T *ptr) {
return dynamic_cast<const Base*>(ptr) != nullptr;
}
E...
Timer function to provide time in nano seconds using C++
...e QueryPerformanceCounter. And here is more on QPC
Apparently there is a known issue with QPC on some chipsets, so you may want to make sure you do not have those chipset. Additionally some dual core AMDs may also cause a problem. See the second post by sebbbi, where he states:
QueryPerformance...
How do I check if a Sql server string is null or empty
...ffer_Text == '')
temp := null;
else
temp := listing.Offer_Text; // may now be null or non-null, but not ''
// b) ISNULL:
if (temp is null)
result := true;
else
result := false;
share
|
impr...
Install dependencies globally and locally using package.json
...abel locally
Then in package.json:
// devDependencies has mocha and babel now
"scripts": {
"test": "mocha",
"build": "babel -d lib src",
"prepublish": "babel -d lib src"
}
Then at your command prompt you can run:
npm run build # finds babel
npm test # finds mocha
npm publish # will run bab...
MongoDB: Combine data from multiple collections into one..how?
...collection called users_comments that contains the merged data and you can now use that. These reduced collections all have _id which is the key you were emitting in your map functions and then all of the values are a sub-object inside the value key - the values aren't at the top level of these red...
How do you use version control with Access development?
...ercase spelling. For example: every file that once contained "OrderNumber" now contains "Ordernumber" in the export and is therefore marked as "changed" (at least by SVN, didn't try other SCM yet). Any idea how I can avoid this? Thanks a lot!
– Christian Specht
...
Are arrays in PHP copied as value or as reference to new variables, and when passed to functions?
... // $arr1 is still array(2, 3)
$arr3 = &$arr1;
$arr3[] = 4; // now $arr1 and $arr3 are the same
?>
For the first part, the best way to be sure is to try ;-)
Consider this example of code :
function my_func($a) {
$a[] = 30;
}
$arr = array(10, 20);
my_func($arr);
var_dump($arr...