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setState vs replaceState in React.js
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With setState the current and previous states are merged. With replaceState, it throws out the current state, and replaces it with only what you provide. Usually setState is used unless you really need to remove keys for som...
Can you determine if Chrome is in incognito mode via a script?
Is it possible to determine if Google Chrome is in incognito mode via a script?
10 Answers
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Bash script error [: !=: unary operator expected
...am trying to error check if the first and only argument is equal to -v but it is an optional argument. I use an if statement but I keep getting the unary operator expected error.
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Split delimited strings in a column and insert as new rows [duplicate]
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Here is another way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split =...
Solving a “communications link failure” with JDBC and MySQL [duplicate]
.... I have tested many approaches that have been mentioned in different web sites, but non of them worked. Finally I changed my code and found out what was the problem. I'll try to tell you about different approaches and sum them up here.
While I was seeking the internet to find the solution for this...
How to merge 2 JSON objects from 2 files using jq?
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Since 1.4 this is now possible with the * operator. When given two objects, it will merge them recursively. For example,
jq -s '.[0] * .[1]' file1 file2
Important: Note the -s (--slurp) flag, which puts files in the same array.
Would get you:
{
"valu...
Why is Python 3.x's super() magic?
In Python 3.x, super() can be called without arguments:
1 Answer
1
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scp (secure copy) to ec2 instance without password
...e an EC2 instance running (FreeBSD 9 AMI ami-8cce3fe5), and I can ssh into it using my amazon-created key file without password prompt, no problem.
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Installing python module within code
I need to install a package from PyPi straight within my script.
Maybe there's some module or distutils ( distribute , pip etc.) feature which allows me to just execute something like pypi.install('requests') and requests will be installed into my virtualenv.
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How to compare two floating point numbers in Bash?
I am trying hard to compare two floating point numbers within a bash script. I have to variables, e.g.
17 Answers
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