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How do I set a variable to the output of a command in Bash?
... be done with $(command) or "$(command)", which I find easier to read, and allows for nesting.
OUTPUT=$(ls -1)
echo "${OUTPUT}"
MULTILINE=$(ls \
-1)
echo "${MULTILINE}"
Quoting (") does matter to preserve multi-line variable values; it is optional on the right-hand side of an assignment, as w...
How can I get the list of files in a directory using C or C++?
...
In small and simple tasks I do not use boost, I use dirent.h which is also available for windows:
DIR *dir;
struct dirent *ent;
if ((dir = opendir ("c:\\src\\")) != NULL) {
/* print all the files and directories within director...
Python None comparison: should I use “is” or ==?
...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects)
In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity:
lst = [1,2,3]
lst == lst[:] # This is Tr...
JavaScript function similar to Python range()
...uple of additional defensive checks - ensure that the arguments passed are all coercible to numbers and ensure that stop is greater than start (and swap them if not).
– Russ Cam
Nov 25 '11 at 18:46
...
Do I have to guard against SQL injection if I used a dropdown?
... make sure the posted size is what you expect.
$possibleOptions = array('All', 'Large', 'Medium', 'Small');
if(in_array($_POST['size'], $possibleOptions)) {
// Expected
} else {
// Not Expected
}
Then use mysqli_* if you are using a version of php >= 5.3.0 which you should be, to sav...
Best way to merge two maps and sum the values of same key?
...mutable.Map[Int,Int] = Map(1 -> 109, 3 -> 300, 2 -> 20)
Specifically, the binary operator for Map[K, V] combines the keys of the maps, folding V's semigroup operator over any duplicate values. The standard semigroup for Int uses the addition operator, so you get the sum of values for eac...
Difference between RegisterStartupScript and RegisterClientScriptBlock?
...:
a. When you use RegisterStartupScript, it will render your script after all the elements in the page (right before the form's end tag). This enables the script to call or reference page elements without the possibility of it not finding them in the Page's DOM.
Here is the rendered source of the ...
PHP abstract properties
...get_class($this) . ' must have a $tablename');
}
}
To enforce this for all derived classes of Foo_Abstract you would have to make Foo_Abstract's constructor final, preventing overriding.
You could declare an abstract getter instead:
abstract class Foo_Abstract {
abstract public function get_...
What is an example of the simplest possible Socket.io example?
...ovided this answer. That being said, here is the original answer updated small-small for the newer API.
Just because I feel nice today:
index.html
<!doctype html>
<html>
<head>
<script src='/socket.io/socket.io.js'></script>
<script>
...
How to assert two list contain the same elements in Python? [duplicate]
...
Thanks. But downright misleading, I would have called it!
– Wild Pottok
Oct 22 '18 at 16:18
...