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In mongoDb, how do you remove an array element by its index?
.../browse/SERVER-1014 , you may vote for it.
The workaround is using $unset and then $pull:
db.lists.update({}, {$unset : {"interests.3" : 1 }})
db.lists.update({}, {$pull : {"interests" : null}})
Update: as mentioned in some of the comments this approach is not atomic and can cause some race con...
AngularJS HTTP post to PHP and undefined
...ngularjs setting of application/json as header, read the raw input in PHP, and then deserialize the JSON.
That can be achieved in PHP like this:
$postdata = file_get_contents("php://input");
$request = json_decode($postdata);
$email = $request->email;
$pass = $request->password;
Alternatel...
Commit only part of a file in Git
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You can use git add --patch <filename> (or -p for short), and git will begin to break down your file into what it thinks are sensible "hunks" (portions of the file). It will then prompt you with this question:
Stage this hunk [y,n,q,a,d,/,j,J,g,s,e,?]?
Here is a description of ea...
Scala: What is the difference between Traversable and Iterable traits in Scala collections?
I have looked at this question but still don't understand the difference between Iterable and Traversable traits. Can someone explain ?
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Do I cast the result of malloc?
...'t cast the result, since:
It is unnecessary, as void * is automatically and safely promoted to any other pointer type in this case.
It adds clutter to the code, casts are not very easy to read (especially if the pointer type is long).
It makes you repeat yourself, which is generally bad.
It can h...
Circular gradient in android
...ying to make a gradient that emits from the middle of the screen in white, and turns to black as it moves toward the edges of the screen.
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See changes to a specific file using git
I know that I can use the git diff command to check the changes, but, as far as I understood, it is directory based. This means it gives all the changes of all files on the current directory.
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【教学】AppInventor2人工智能应用：Personal Image Classifier (PIC) Tool...
繁体中文原文：https://blog.cavedu.com/2019/08/27/app-inventor-image-classifier/
[color=var(--fs-experimental-link-color)][color=var(--fs-color-primary)]27
[size=0.8em]8 月
MIT App Inventor 團隊蠻早就發佈了 [color=var(--fs-experimental-link-color)]look extension，概念上...
How do I sort a vector of pairs based on the second element of the pair?
...to your question, here's some thoughts ...
if you really wanna be creative and be able to reuse this concept a lot, just make a template:
template <class T1, class T2, class Pred = std::less<T2> >
struct sort_pair_second {
bool operator()(const std::pair<T1,T2>&left, const...
How can I delete a newline if it is the last character in a file?
...line if it is the last character in a file. od -c shows me that the command I run does write the file with a trailing new line:
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