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Java Enum Methods - return opposite direction enum
...like to declare an enum Direction, that has a method that returns the opposite direction (the following is not syntactically correct, i.e, enums cannot be instantiated, but it illustrates my point). Is this possible in Java?
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Update R using RStudio
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You install a new version of R from the official website.
RStudio should automatically start with the new version when you relaunch it.
In case you need to do it manually, in RStudio, go to :Tools -> options -> General.
Check @micstr's answer for a more detailed walkth...
Change key pair for ec2 instance
...thanks to Eric Hammond's blog post:
Stop the running EC2 instance
Detach its /dev/xvda1 volume (let's call it volume A) - see here
Start new t1.micro EC2 instance, using my new key pair. Make sure you create it in the same subnet, otherwise you will have to terminate the instance and create it aga...
Is there a good reason to use upper case for SQL keywords? [closed]
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It's just a matter of style, probably originating in the days when editors didn't do code colouring.
I used to prefer all upper case, but I'm now leaning towards all lower.
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Update Git branches from master
I'm new to Git, and now I'm in this situation:
9 Answers
9
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Convert list to array in Java [duplicate]
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Either:
Foo[] array = list.toArray(new Foo[0]);
or:
Foo[] array = new Foo[list.size()];
list.toArray(array); // fill the array
Note that this works only for arrays of reference types. For arrays of primitive types, use...
What is the difference between `let` and `var` in swift?
...Answer cannot be changed afterwards. This is why anything weak can't be written using let. They need to change during runtime and you must be using var instead.
The var defines an ordinary variable.
What is interesting:
The value of a constant doesn’t need to be known at compile time, but y...
Can an AngularJS controller inherit from another controller in the same module?
Within a module, a controller can inherit properties from an outside controller:
9 Answers
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Java 8 Iterable.forEach() vs foreach loop
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The better practice is to use for-each. Besides violating the Keep It Simple, Stupid principle, the new-fangled forEach() has at least the following deficiencies:
Can't use non-final variables. So, code like the following can't be turned into a forEach lambda:
Object prev = null;
for(Obje...
Iterate a list as pair (current, next) in Python
I sometimes need to iterate a list in Python looking at the "current" element and the "next" element. I have, till now, done so with code like:
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