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'AND' vs '&&' as operator
I have a codebase where developers decided to use AND and OR instead of && and || .
10 Answers
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When exactly is it leak safe to use (anonymous) inner classes?
I have been reading some articles on memory leaks in Android and watched this interesting video from Google I/O on the subject .
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Express.js - app.listen vs server.listen
... get it. What is the difference between creating an app using Express.js and starting the app listening on port 1234, for example:
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Is it better to use std::memcpy() or std::copy() in terms to performance?
...ll have a slight, almost imperceptible performance loss. I just did a test and found that to be untrue: I did notice a performance difference. However, the winner was std::copy.
I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and ...
How to prune local tracking branches that do not exist on remote anymore
...es.
This line should do the trick (requires bash or zsh, won't work with standard Bourne shell):
git branch -r | awk '{print $1}' | egrep -v -f /dev/fd/0 <(git branch -vv | grep origin) | awk '{print $1}' | xargs git branch -d
This string gets the list of remote branches and passes it into egrep...
How to convert a string to lower case in Bash?
...
The are various ways:
POSIX standard
tr
$ echo "$a" | tr '[:upper:]' '[:lower:]'
hi all
AWK
$ echo "$a" | awk '{print tolower($0)}'
hi all
Non-POSIX
You may run into portability issues with the following examples:
Bash 4.0
$ echo "${a,,}"
hi all...
Is it faster to count down than it is to count up?
... to count down than to count up.
For example if you need to use a FOR loop and the loop index is not used somewhere (like printing a line of N * to the screen)
I mean that code like this:
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Large, persistent DataFrame in pandas
I am exploring switching to python and pandas as a long-time SAS user.
6 Answers
6
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Java ArrayList copy
... l1 of size 10. I assign l1 to new list reference type l2 . Will l1 and l2 point to same ArrayList object? Or is a copy of the ArrayList object assigned to l2 ?
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Which would be better for concurrent tasks on node.js? Fibers? Web-workers? or Threads?
I stumbled over node.js sometime ago and like it a lot. But soon I found out that it lacked badly the ability to perform CPU-intensive tasks. So, I started googling and got these answers to solve the problem: Fibers, Webworkers and Threads (thread-a-gogo). Now which one to use is a confusion and one...