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How do you do a ‘Pause’ with PowerShell 2.0?
...omments on this page). I made two slight improvements to the latter: added Test-Path to avoid an error if you use Set-StrictMode (you do, don't you?!) and the final Write-Host to add a newline after your keystroke to put the prompt in the right place.
Function Pause ($Message = "Press any key to co...
Quick-and-dirty way to ensure only one instance of a shell script is running at a time
... This isn't atomic and is thus useless. You need an atomic mechanism for test & set.
– K Richard Pixley
Mar 31 '17 at 17:56
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show 6 m...
Merge two Git repositories without breaking file history
...d add the old remote repository.
git clone https://github.com/alexbr9007/Test.git
cd Test
git remote add OldRepo https://github.com/alexbr9007/Django-React.git
git remote -v
Fetch for all the files from the old repo so a new branch gets created.
git fetch OldRepo
git branch -a
In the master b...
How do I replace NA values with zeros in an R dataframe?
...ults.
If you are struggling with massive dataframes, data.table is the fastest option of all: 40% faster than the standard Base R approach. It also modifies the data in place, effectively allowing you to work with nearly twice as much of the data at once.
A clustering of other helpful tidyverse ...
Curious null-coalescing operator custom implicit conversion behaviour
...
return new C();
}
public static void Main() {
C? test = (X() ?? Y()) ?? Z();
}
}
This code will output:
X()
X()
A to B (0)
X()
X()
A to B (0)
B to C (0)
That made me think that the first part of each ?? coalesce expression is evaluated twice.
This code proved it:
...
Calling C++ class methods via a function pointer
.../ Get a method pointer.
int (C::*p)(int) = &C::m;
// Create a test object.
C c(1);
C *cp = &c;
// Operator .*
assert((c.*p)(2) == 3);
// Operator ->*
assert((cp->*p)(2) == 3);
}
Compile and run:
g++ -ggdb3 -O0 -std=c++11 -Wall -Wextra -pedantic -o ...
Python logging not outputting anything
... level=logging.DEBUG) logger = logging.getLogger() logger.info('Test B') logging.info('Test A')
– Rylan Schaeffer
Aug 11 at 15:39
...
NSRange to Range
...he delegate callback, and so this is safe to use, but I haven't personally tested it.
– Alex Pretzlav
Jan 6 '15 at 21:33
2
...
How does HTTP file upload work?
...each one.
You can produce examples using:
nc -l or an ECHO server: HTTP test server accepting GET/POST requests
an user agent like a browser or cURL
Save the form to a minimal .html file:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8"/>
<title>u...
Ship an application with a database
...where it can be accessed and
* handled. This is done by transfering bytestream.
* */
private void copyDataBase() throws IOException {
/*
* Close SQLiteOpenHelper so it will commit the created empty database
* to internal storage.
*/
close();
...