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How to tell if a tag failed to load
... };
var fail = function () {
if (!scriptTag.__es) {
scriptTag.__es = true;
scriptTag.id = 'failed';
args.failure(scriptTag);
}
};
scriptTag.onload = function () {
...
Extending the User model with custom fields in Django
...o.contrib.auth.models import User
from django.db.models.signals import post_save
class UserProfile(models.Model):
user = models.OneToOneField(User)
#other fields here
def __str__(self):
return "%s's profile" % self.user
def create_user_profile(sender, instance, creat...
What is the difference between AF_INET and PF_INET in socket programming?
What is the difference between AF_INET and PF_INET in socket programming?
7 Answers
7
...
Remove empty elements from an array in Javascript
...filter(function(e){return e});
Return:
["hello", 1, 100, " "]
UPDATE (based on Alnitak's comment)
In some situations you may want to keep "0" in the array and remove anything else (null, undefined and ""), this is one way:
arr.filter(function(e){ return e === 0 || e });
Return:
["hello", 0...
Why can templates only be implemented in the header file?
... sentence at the very start of this answer to clarify that the question is based on a false premise. If somebody asks "Why is X true?" when in fact X is not true, we should quickly reject that assumption.
– Aaron McDaid
Aug 5 '15 at 9:39
...
data.table vs dplyr: can one do something well the other can't or does poorly?
...n shallow copied DT
DT[x > 2L, x := 3L] ## have to copy (like base R / dplyr does always); otherwise original DT will
## also get modified.
}
By not using shallow(), the old functionality is retained:
bar <- function(DT) {
DT[, newcol := 1L] ...
_DEBUG vs NDEBUG
...
Visual Studio defines _DEBUG when you specify the /MTd or /MDd option, NDEBUG disables standard-C assertions. Use them when appropriate, ie _DEBUG if you want your debugging code to be consistent with the MS CRT debugging techniques and NDEBUG if ...
PDO Prepared Inserts multiple rows in single query
...
$pdo->beginTransaction(); // also helps speed up your inserts.
$insert_values = array();
foreach($data as $d){
$question_marks[] = '(' . placeholders('?', sizeof($d)) . ')';
$insert_values = array_merge($insert_values, array_values($d));
}
$sql = "INSERT INTO table (" . implode(",", $...
How to downgrade or install an older version of Cocoapods
...0.25.0
You can use older installed versions with following command:
pod _0.25.0_ setup
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How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
...e + operator, which returns the concatenation of the lists:
concat = first_list + second_list
One disadvantage of this method is that twice the memory is now being used . For very large lists, depending on how you're going to use it once it's created, itertools.chain might be your best bet:
>&...