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Checking if sys.argv[x] is defined
What would be the best way to check if a variable was passed along for the script:
8 Answers
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Is the ternary operator faster than an “if” condition in Java [duplicate]
I am prone to " if-conditional syndrome " which means I tend to use if conditions all the time. I rarely ever use the ternary operator. For instance:
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How to exit if a command failed?
...am a noob in shell-scripting. I want to print a message and exit my script if a command fails. I've tried:
8 Answers
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How to know if user is logged in with passport.js?
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If user is logged in, passport.js will create user object in req for every request in express.js, which you can check for existence in any middleware:
if (req.user) {
// logged in
} else {
// not logged in
}
You ca...
Split List into Sublists with LINQ
...By(x=>f(x)).First() will never yield a group. OP asked about lists, but if we write to work with IEnumerable, making only a single iteration, we reap the performance advantage.
– Colonel Panic
Jul 11 '12 at 22:16
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Are non-synchronised static methods thread safe if they don't modify static class variables?
I was wondering if you have a static method that is not synchronised, but does not modify any static variables is it thread-safe? What about if the method creates local variables inside it? For example, is the following code thread-safe?
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Determine if two rectangles overlap each other?
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if (RectA.Left < RectB.Right && RectA.Right > RectB.Left &&
RectA.Top > RectB.Bottom && RectA.Bottom < RectB.Top )
or, using Cartesian coordinates
(With X1 being left coord, X...
Cannot truncate table because it is being referenced by a FOREIGN KEY constraint?
Using MSSQL2005, can I truncate a table with a foreign key constraint if I first truncate the child table (the table with the primary key of the FK relationship)?
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Copy entire contents of a directory to another using php
... @mkdir($dst);
while(false !== ( $file = readdir($dir)) ) {
if (( $file != '.' ) && ( $file != '..' )) {
if ( is_dir($src . '/' . $file) ) {
recurse_copy($src . '/' . $file,$dst . '/' . $file);
}
else {
c...
Create Django model or update if exists
I want to create a model object, like Person, if person's id doesn't not exist, or I will get that person object.
6 Answer...