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Is List a subclass of List? Why are Java generics not implicitly polymorphic?
... of dogs. A list of dogs is only a list of animals if you consider it in a read-only sense.
– Jon Skeet
Jan 28 '13 at 19:33
13
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Alternate FizzBuzz Questions [closed]
...
I've been reading you answer for a while and could,'t figure out what was going on, why didn't I like it, the thing is your questions are not fun to code :) (which is ok since this were intended for interviews). There is no real point ...
What is an uninterruptible process?
...rstand the concept of an interruptible system call. The classic example is read(). This is a system call that can take a long time (seconds) since it can potentially involve spinning up a hard drive, or moving heads. During most of this time, the process will be sleeping, blocking on the hardware.
...
Why are side-effects modeled as monads in Haskell?
...ld -> ((), RealWorld)
We want to
get a filename from the console,
read that file, and
print that file's contents to the console.
How would we do it if we could access the real world states?
printFile :: RealWorld -> ((), RealWorld)
printFile world0 = let (filename, world1) = getLine wor...
Most underused data visualization [closed]
...y agree with the other posters: Tufte's books are fantastic and well worth reading.
First, I would point you to a very nice tutorial on ggplot2 and ggobi from "Looking at Data" earlier this year. Beyond that I would just highlight one visualization from R, and two graphics packages (which are no...
Why use JUnit for testing?
...ts, poring over millions of log lines across dozens of files and machines, reading generated and delivered emails, checking text messages, checking the path of a robot, filling a bottle of soda, aggregating data from a hundred web services, checking the audit trail of a financial transaction... you...
How to use Elasticsearch with MongoDB?
...host" : "127.0.0.1:27017" } ] }
rs.initiate(config)
rs.slaveOk() // allows read operations to run on secondary members.
Now install Elasticsearch. I'm just following this helpful Gist.
Make sure Java is installed.
sudo apt-get install openjdk-7-jre-headless -y
Stick with v1.1.x for now until t...
Difference between open and codecs.open in Python
.../docs.python.org/3.4/library/io.html
Now, for the original question: when reading text (including "plain text", HTML, XML and JSON) in Python 2 you should always use io.open() with an explicit encoding, or open() with an explicit encoding in Python 3. Doing so means you get correctly decoded Unicod...
How to set environment variables in Python?
... only the way your program's children run. True, your program can set and read back environment variables, but only from the environment it configures for its children. See also: change current process environment. So far I haven't found a way for a Python script to modify its parent env.
...
std::unique_lock or std::lock_guard?
...ch needs mutual exclusion (e.g. open the same
file in multiple threads).
*/
//mutex is automatically released when lock goes out of scope
};
To clarify a question by chmike, by default std::lock_guard and std::unique_lock are the same.
So in the above case, yo...