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Is cout synchronized/thread-safe?
...f particular interest here is the fact that cout is buffered. Even if the calls to write (or whatever it is that accomplishes that effect in that particular implementation) are guaranteed to be mutually exclusive, the buffer might be shared by the different threads. This will quickly lead to corrupt...
center aligning a fixed position div
...ake a new static div with margin-left: auto and margin-right: auto, or for table make it align="center".
Tadaaaah, you have centered your fixed div now
Hope this will help.
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Retina displays, high-res background images
...e load, will have higher power consumption resizing the image (and Nexus 7 tables are quite known for random reboots), and consume more bandwidth. So, I'd recommend sticking with @2x only being served to 2dppx+ clients.
– cnst
Apr 13 '16 at 20:53
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How to chain scope queries with OR instead of AND?
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Use ARel
t = Person.arel_table
results = Person.where(
t[:name].eq("John").
or(t[:lastname].eq("Smith"))
)
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Macro vs Function in C
...uct webpage page;
page.numButtons = 2;
num_button_holes(page) -> 8
Finally, macros can be difficult to debug, producing weird syntax errors or runtime errors that you have to expand to understand (e.g. with gcc -E), because debuggers cannot step through macros, as in this example:
#define prin...
AI2 Keep Awake
...eping your Android application running when the device wants to sleep . Table of contents Download Test results WakeLock WifiLock Battery optimization Foreground service Usage Request WakeLock Multiple WakeLocks Notification / Notification Channels NotificationChannel Notification N...
Simplest way to detect a mobile device in PHP
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@kavior.com Yes it can be faked, but we should allow people to fake if they wish... because that would be their intention, why stop people from doing what they specifically want (i.e. load the desktop version for some reason in particular)?
– Nick St...
Dealing with commas in a CSV file
...any easily-available csv library - that is to say RFC 4180.
There's actually a spec for CSV format and how to handle commas:
Fields containing line breaks (CRLF), double quotes, and commas should be enclosed in double-quotes.
http://tools.ietf.org/html/rfc4180
So, to have values foo and ...
Find MongoDB records where array field is not empty
All of my records have a field called "pictures". This field is an array of strings.
11 Answers
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How do you serialize a model instance in Django?
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You can easily use a list to wrap the required object and that's all what django serializers need to correctly serialize it, eg.:
from django.core import serializers
# assuming obj is a model instance
serialized_obj = serializers.serialize('json', [ obj, ])
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