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Does MongoDB's $in clause guarantee order
...d index order as shown.
If you need to preserve this order, then you basically have two options.
So 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 ];
...
How to use Boost in Visual Studio 2010
...te's answer is pretty good already, I'm going to expand on it more specifically for Visual Studio 2010 as requested, and include information on compiling in the various optional components which requires external libraries.
If you are using headers only libraries, then all you need to do is to unar...
When to use setAttribute vs .attribute= in JavaScript?
...
This answer is not clear enough...I don't really feel I understand this yet.
– temporary_user_name
Oct 24 '13 at 21:48
1
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Why is __init__() always called after __new__()?
... new instance.
__new__ is the first step of instance creation. It's called first, and is
responsible for returning a new
instance of your class.
In contrast,
__init__ doesn't return anything; it's only responsible for initializing the
instance after it's been created.
In ge...
Map vs Object in JavaScript
...stored at a key. Because of this, Objects have been used as Maps
historically; however, there are important differences between Objects
and Maps that make using a Map better.
An Object has a prototype, so there are default keys in the map.
However, this can be bypassed using map = Object....
What does “#define _GNU_SOURCE” imply?
...
For exact details on what are all enabled by _GNU_SOURCE, documentation can help.
From the GNU documentation:
Macro: _GNU_SOURCE
If you define this macro, everything is included: ISO C89, ISO C99, POSIX.1, POSIX.2, BSD, SVID, X/Open, LFS, and ...
Get a filtered list of files in a directory
...t a list of files in a directory using Python, but I do not want a list of ALL the files.
14 Answers
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Should I use Vagrant or Docker for creating an isolated environment? [closed]
...I think Docker is what you want.
Vagrant is a virtual machine manager. It allows you to script the virtual machine configuration as well as the provisioning. However, it is still a virtual machine depending on VirtualBox (or others) with a huge overhead. It requires you to have a hard drive file th...
Django: Get list of model fields?
...s which (ultimately) inherits from models.Model . I want to get a list of all the fields defined for this model. For example, phone_number = CharField(max_length=20) . Basically, I want to retrieve anything that inherits from the Field class.
...
How do I determine the size of an object in Python?
...turn the size of an object in bytes.
The object can be any type of object.
All built-in objects will return
correct results, but this does not
have to hold true for third-party
extensions as it is implementation
specific.
Only the memory consumption directly attributed to the object is
accounted for...