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Validating IPv4 addresses with regexp
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List changes unexpectedly after assignment. How do I clone or copy it to prevent this?
...it does not make sense to use it ever. ;) (In his opinion, the next one is more readable).
You can use the built in list() function:
new_list = list(old_list)
You can use generic copy.copy():
import copy
new_list = copy.copy(old_list)
This is a little slower than list() because it has to find o...
What is “:-!!” in C code?
...to fail the build.
The macro is somewhat misnamed; it should be something more like BUILD_BUG_OR_ZERO, rather than ...ON_ZERO. (There have been occasional discussions about whether this is a confusing name.)
You should read the expression like this:
sizeof(struct { int: -!!(e); }))
(e): Comput...
What is the PostgreSQL equivalent for ISNULL()
...CT CASE WHEN field IS NULL THEN 'Empty' ELSE field END AS field_alias
Or more idiomatic:
SELECT coalesce(field, 'Empty') AS field_alias
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Domain Driven Design: Domain Service, Application Service
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117
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Spring Boot - inject map from application.yml
..., controlling how missing properties are handled, etc. See the javadoc for more information.
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Performance of foreach, array_map with lambda and array_map with static function
...are with mcfedr's answer below for additional results without XDebug and a more recent PHP version.
function lap($func) {
$t0 = microtime(1);
$numbers = range(0, 1000000);
$ret = $func($numbers);
$t1 = microtime(1);
return array($t1 - $t0, $ret);
}
function useForeach($numbers) {
$re...
Microsecond timing in JavaScript
...i7 system, I've been able to reliably get the exact same millisecond, over more than 1,000 attempts. Only when I'm trying to do things like load an extra web page, or other, the millisecond accuracy degrades (And I'm able to successfully catch my own degraded accuracy by doing a before-and-after ti...
Is it safe to delete a void pointer?
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147
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Removing duplicate rows in vi?
...)\(\n\1\)\+$/\1/
It searches for any line immediately followed by one or more copies of itself, and replaces it with a single copy.
Make a copy of your file though before you try it. It's untested.
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