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How to convert a factor to integer\numeric without loss of information?
...nction in your global environment, but you might cause problems if you actually register it as an S3 method.
– Joshua Ulrich
Apr 18 '14 at 12:03
1
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Command to get nth line of STDOUT
...ssage:
ls -l | sed -n -e '2{p;q}'
I've seen that often enough that I usually use the first (which is easier to type, anyway), though ls is not a command that complains when it gets SIGPIPE.
For a range of lines:
ls -l | sed -n 2,4p
For several ranges of lines:
ls -l | sed -n -e 2,4p -e 20,30...
How to find reason of failed Build without any error or warning
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Excellent find Richard - Really useful information when you set both verbosity levels to diagnostic
– Dai Bok
Oct 20 '16 at 8:38
3
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CORS: Cannot use wildcard in Access-Control-Allow-Origin when credentials flag is true
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This is a part of security, you cannot do that. If you want to allow credentials then your Access-Control-Allow-Origin must not use *. You will have to specify the exact protocol + domain + port. For reference see these questions :
Access-Control-Allow-Origin wildcard subdomains, ports...
Why is a combiner needed for reduce method that converts type in java 8
... got - argument mismatch; int cannot be converted to java.lang.String. Actually, I think passing 0 as the identity value is also wrong here, since a String is expected (T).
Also note that this version of reduce processes a stream of Ts and returns a T, so you can't use it to reduce a stream of Stri...
F12 no longer works in Visual Studio
This is driving me crazy. Ever since I installed ReSharper 4, F12 no longer seems to work. If you look at the all the ReSharper short cuts in the Goto sub menu Declaration doesn't have any assigned!
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Which one will execute faster, if (flag==0) or if (0==flag)?
...n :)
The answer is:
What is flag's type?
In the case where flag actually is a user-defined type. Then it depends on which overload of operator== is selected. Of course it can seem stupid that they would not be symmetric, but it's certainly allowed, and I have seen other abuses already.
If fl...
How to create custom easing function with Core Animation?
... function easier using two new timing objects.
1) UICubicTimingParameters allows to define cubic Bézier curve as an easing function.
let cubicTimingParameters = UICubicTimingParameters(controlPoint1: CGPoint(x: 0.25, y: 0.1), controlPoint2: CGPoint(x: 0.25, y: 1))
let animator = UIViewPropertyAni...
How do I pass a unique_ptr argument to a constructor or a function?
...e_ptr<Base> n)
: next(std::move(n)) {}
In order for the user to call this, they must do one of the following:
Base newBase(std::move(nextBase));
Base fromTemp(std::unique_ptr<Base>(new Base(...));
To take a unique pointer by value means that you are transferring ownership of the p...
Naming threads and thread-pools of ExecutorService
...ified, a Executors.defaultThreadFactory() is used, that creates threads to all be in the same ThreadGroup and with the same NORM_PRIORITY priority and non-daemon status. By supplying a different ThreadFactory, you can alter the thread's name, thread group, priority, daemon status, etc. If a ThreadFa...