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How to create a file in Linux from terminal window? [closed]
... want the file to contain:
touch /path/to/file for an empty file
somecommand > /path/to/file for a file containing the output of some command.
eg: grep --help > randomtext.txt
echo "This is some text" > randomtext.txt
nano /path/to/file or vi /path/to/file (or any other editor e...
How to implement __iter__(self) for a container object (Python)
... to the sequence.
The following will create an iterator that yields five, and then every item in some_list.
def __iter__(self):
yield 5
yield from some_list
Pre-3.3, yield from didn't exist, so you would have to do:
def __iter__(self):
yield 5
for x in some_list:
yield x
...
Adding a newline into a string in C#
...
@Alexander I'd say that string operations being inefficient is a problem we don't have to worry anymore in 2019.
– Filipe Madureira
Dec 4 '19 at 12:54
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How to use the pass statement?
I am in the process of learning Python and I have reached the section about the pass statement. The guide I'm using defines it as being a Null statement that is commonly used as a placeholder.
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When is memoization automatic in GHC Haskell?
... in foldl' (+) 0 (y ++ [x])
GHC might notice that y does not depend on x and rewrite the function to
f = let y = [1..30000000] in \x -> foldl' (+) 0 (y ++ [x])
In this case, the new version is much less efficient because it will have to read about 1 GB from memory where y is stored, while th...
Python threading.timer - repeat function every 'n' seconds
I want to fire off a function every 0.5 seconds and be able to start and stop and reset the timer. I'm not too knowledgeable of how Python threads work and am having difficulties with the python timer.
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How to install latest version of Node using Brew
...ew update first? If you don't do that, Homebrew can't update its formulas, and if it doesn't update its formulas it doesn't know how to install the latest versions of software.
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What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
Why were 181783497276652981 and 8682522807148012 chosen in Random.java ?
3 Answers
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Listing only directories using ls in Bash?
This command lists directories in the current path: ls -d */
26 Answers
26
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What does “coalgebra” mean in the context of programming?
I have heard the term "coalgebras" several times in functional programming and PLT circles, especially when the discussion is about objects, comonads, lenses, and such. Googling this term gives pages that give mathematical description of these structures which is pretty much incomprehensible to me. ...