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How to detect Safari, Chrome, IE, Firefox and Opera browser?
...it's truly necessary, such as showing browser-specific instructions to install an extension. Use feature detection when possible.
Demo: https://jsfiddle.net/6spj1059/
// Opera 8.0+
var isOpera = (!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(' OPR/') >...
Execute code when Django starts ONCE only?
... entirely a separate problem. The idea of special one-time startup before all management commands is hard to understand. You'll have to provide something specific. Perhaps in another question.
– S.Lott
Feb 13 '12 at 12:49
...
Programmatically saving image to Django ImageField
...import File # you need this somewhere
import urllib
# The following actually resides in a method of my model
result = urllib.urlretrieve(image_url) # image_url is a URL to an image
# self.photo is the ImageField
self.photo.save(
os.path.basename(self.url),
File(open(result[0], 'rb'))
...
How to check iOS version?
...system version as an indication of device or OS capabilities. There is usually a more reliable method of checking whether a particular feature or class is available.
Checking for the presence of APIs:
For example, you can check if UIPopoverController is available on the current device using NSCla...
Setting environment variables on OS X
... extensive research and if you want to set variables that are available in all GUI applications, your only option is /etc/launchd.conf.
Please note that environment.plist does not work for applications launched via Spotlight. This is documented by Steve Sexton here.
Open a terminal prompt
Type su...
How to detect the current OS from Gradle
... |
edited Dec 4 '19 at 11:53
Peter Mortensen
26.5k2121 gold badges9292 silver badges122122 bronze badges
...
Why do people say there is modulo bias when using a random number generator?
...AND_MAX is 10 and I decide to generate a random number between 0 and 2 by calling rand()%3. However, rand()%3 does not produce the numbers between 0 and 2 with equal probability!
When rand() returns 0, 3, 6, or 9, rand()%3 == 0. Therefore, P(0) = 4/11
When rand() returns 1, 4, 7, or 10, rand()%3 ...
Unmount the directory which is mounted by sshfs in Mac [closed]
...
answered Apr 7 '14 at 19:11
palswimpalswim
10.5k66 gold badges4545 silver badges7070 bronze badges
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Test if a variable is a list or tuple
... excludes custom sequences, iterators, and other things that you might actually need. However, sometimes you need to behave differently if someone, for instance, passes a string. My preference there would be to explicitly check for str or unicode like so:
import types
isinstance(var, types.String...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
...
Yes, __attribute__((packed)) is potentially unsafe on some systems. The symptom probably won't show up on an x86, which just makes the problem more insidious; testing on x86 systems won't reveal the problem. (On the x86, misaligned accesses are handled in hardwa...