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Why shouldn't Java enum literals be able to have generic type parameters?
... the latter because of type erasure. But there is one thing I don't understand, Why can't I create an enum like this:
7 Ans...
Why does 2 mod 4 = 2?
...ion. My term does not start for two more weeks so I can't ask a professor, and the suspense would kill me.
19 Answers
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The way to check a HDFS directory's size?
...
Prior to 0.20.203, and officially deprecated in 2.6.0:
hadoop fs -dus [directory]
Since 0.20.203 (dead link) 1.0.4 and still compatible through 2.6.0:
hdfs dfs -du [-s] [-h] URI [URI …]
You can also run hadoop fs -help for more info and...
Identifying and removing null characters in UNIX
...nulls
If you are wondering if input redirection in the middle of the command arguments works, it does. Most shells will recognize and deal with I/O redirection (<, >, …) anywhere in the command line, actually.
shar...
How to keep a git branch in sync with master
...git checkout master
git merge mobiledevicesupport
git push origin master
and thats it.
the assumption here is that mobilexxx is a topic branch with work that isn't ready to go into your main branch yet. So only merge into master when mobiledevicesupport is in a good place
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Why do we need boxing and unboxing in C#?
Why do we need boxing and unboxing in C#?
11 Answers
11
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PHP random string generator
I'm trying to create a randomized string in PHP, and I get absolutely no output with this:
59 Answers
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Screenshot Apps for iPhone simulator [closed]
... from which version of the iOS Simulator is this possible, but it's better and faster!
You can also try cmd+ctrl+C while in the iOS simulator. Then open Preview or an image editing program and try cmd+N (the image is in the clipboard).
Edit: According to apple's new guidelines we need to provide hig...
Determining if a variable is within range?
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This also works for Date and DateTime objects while === does not.
– Aditya
Jun 4 '12 at 2:23
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Rails: select unique values from a column
...ing)
Result of this is a collection of Model objects. Not plain ratings. And from uniq's point of view, they are completely different. You can use this:
Model.select(:rating).map(&:rating).uniq
or this (most efficient)
Model.uniq.pluck(:rating)
# rails 5+
Model.distinct.pluck(:rating)
U...