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When should I make explicit use of the `this` pointer?
...
Usually, you do not have to, this-> is implied.
Sometimes, there is a name ambiguity, where it can be used to disambiguate class members and local variables. However, here is a completely different case where this-> is e...
How do I get an ISO 8601 date on iOS?
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Use NSDateFormatter:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
NSLocale *enUSPOSIXLocale = [NSLocale localeWithLocaleIdentifier:@"en_US_POSIX"];
[dateFormatter setLocale:enUSPOSIXLocale];
[dateFormatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ssZZZZZ"];
[dateFormatter setCale...
How to show Page Loading div until the page has finished loading?
...ction on our website that loads quite slowly as it's doing some intensive calls.
12 Answers
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Regular expression to match DNS hostname or IP Address?
...o be escaped with \.
ValidHostnameRegex is valid as per RFC 1123. Originally, RFC 952 specified that hostname segments could not start with a digit.
http://en.wikipedia.org/wiki/Hostname
The original specification of
hostnames in RFC
952,
mandated that labels could not start
with a d...
How can I declare and use Boolean variables in a shell script?
......
if [ "$the_world_is_flat" = true ] ; then
echo 'Be careful not to fall off!'
fi
Original Answer
Caveats: https://stackoverflow.com/a/21210966/89391
the_world_is_flat=true
# ...do something interesting...
if $the_world_is_flat ; then
echo 'Be careful not to fall off!'
fi
From: Usi...
How to fix SSL certificate error when running Npm on Windows?
When I try to install a package with npm, it doesn't work. After a long wait, I eventually get an error 'tunneling socket could not be established, sutatusCode=403'.
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What does %~dp0 mean, and how does it work?
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Calling
for /?
in the command-line gives help about this syntax (which can be used outside FOR, too, this is just the place where help can be found).
In addition, substitution of FOR
variable references has been enhan...
How do I get the current username in Windows PowerShell?
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I'd like to throw in the whoami command, which basically is a nice alias for doing %USERDOMAIN%\%USERNAME% as proposed in other answers.
Write-Host "current user:"
Write-Host $(whoami)
share
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Is it possible to break a long line to multiple lines in Python [duplicate]
...ore or after a binary operator, as long as the convention is consistent locally. For new code Knuth's style (line breaks before the operator) is suggested.
Example of explicit line continuation:
a = '1' \
+ '2' \
+ '3' \
- '4'
...
How to change the color of an svg element?
I want to use this technique http://css-tricks.com/svg-fallbacks/ and change the svg color but so far I haven't been able to do so. I put this in the css but my image is always black, no matter what. My code:
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