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Does MongoDB's $in clause guarantee order
...o let's say that you were matching on the values of _id in your documents with an array that is going to be passed in to the $in as [ 4, 2, 8 ].
Approach using Aggregate
var list = [ 4, 2, 8 ];
db.collection.aggregate([
// Match the selected documents by "_id"
{ "$match": {
"...
C# operator overload for `+=`?
...or the Garbage collection and memory management, which is a potential security hole in CLR strong typed world.
Nevertheless, let's see what exactly an operator is. According to the famous Jeffrey Richter's book, each programming language has its own operators list, which are compiled in a special m...
From an array of objects, extract value of a property as array
I have JavaScript object array with the following structure:
16 Answers
16
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What does it mean if a Python object is “subscriptable” or not?
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It basically means that the object implements the __getitem__() method. In other words, it describes objects that are "containers", meaning they contain other objects. This includes strings, lists, tuples, and dictionaries.
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Adding Core Data to existing iPhone project
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So open up Xcode and look for some file like App_Prefix.pch, by default it's in the Other Sources group. After the UIKit import statement, add the following line:
#import <CoreData/CoreData.h>
And you should be ready to go.
Xcode 4
For projects created in Xcode 4, the prefix file can b...
How to add a 'or' condition in #ifdef
How can I add a 'or' condition in #ifdef ?
3 Answers
3
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jsonify a SQLAlchemy result set in Flask [duplicate]
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It seems that you actually haven't executed your query. Try following:
return jsonify(json_list = qryresult.all())
[Edit]: Problem with jsonify is, that usually the objects cannot be jsonified automatically. Even Python's ...
What does `m_` variable prefix mean?
I often see m_ prefix used for variables ( m_World , m_Sprites ,...) in tutorials, examples and other code mainly related to game development.
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Python multiprocessing PicklingError: Can't pickle
I am sorry that I can't reproduce the error with a simpler example, and my code is too complicated to post. If I run the program in IPython shell instead of the regular Python, things work out well.
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error LNK2019: unresolved external symbol _WinMain@16 referenced in function ___tmainCRTStartup
...follow
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edited Mar 19 '15 at 22:28
answered Dec 16 '11 at 10:24
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