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Global and local variables in R
...ction() {
bar <<- 1
}
foo()
bar
In this case bar is accessible from outside the function.
However, unlike C, C++ or many other languages, brackets do not determine the scope of variables. For instance, in the following code snippet:
if (x > 10) {
y <- 0
}
else {
y <- 1...
unable to start mongodb local server
...
Find out from netstat which process is running mongodb port (27017)
command:
sudo netstat -tulpn | grep :27017
Output will be:
tcp 0 0 0.0.0.0:27017 0.0.0.0:*
LISTEN 6432/mongod
In my case "6432" is...
What does the term “porcelain” mean in Git?
...
"Porcelain" is the material from which toilets are usually made (and sometimes other fixtures such as washbasins). This is distinct from "plumbing" (the actual pipes and drains), where the porcelain provides a more user-friendly interface to the plumbin...
Why are Perl 5's function prototypes bad?
...efault list context.)
In particular, they make it hard to pass parameters from arrays. For example:
my @array = qw(a b c);
foo(@array);
foo(@array[0..1]);
foo($array[0], $array[1], $array[2]);
sub foo ($;$$) { print "@_\n" }
foo(@array);
foo(@array[0..1]);
foo($array[0], $array[1], $array[2]);...
What's the difference between findAndModify and update in MongoDB?
...
From the MongoDB docs (emphasis added):
By default, both operations modify a single document. However, the update() method with its multi option can modify more than one document.
If multiple documents match the upda...
Remove warning messages in PHP
...an't fix the problem that generates the warning nor (2) hide your warnings from end users via php error_reporting... Hiding warnings from your developers is NOT a solution.
– Joshua Kissoon
Jun 26 '14 at 11:42
...
When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used?
...gly. It turns one type directly into another — such as casting the value from one pointer to another, or storing a pointer in an int, or all sorts of other nasty things. Largely, the only guarantee you get with reinterpret_cast is that normally if you cast the result back to the original type, you...
git switch branch without discarding local changes
...l:
$ git checkout -b develop
This creates a new develop branch starting from wherever you are
now. Now you can commit and the new stuff is all on develop.
You do have a develop. See if Git will let you switch without
doing anything:
$ git checkout develop
This will either succeed, or complai...
Automatically open Chrome developer tools when new tab/new window is opened
...to-open Developer Tools in Pop-ups if they were open where you opened them from. For example, if you do not have Dev Tools open and you get a popup, it won't open with Dev Tools. But if you Have Dev Tools Open and then you click something, the popup will have Dev-Tools Automatically opened.
UPDATE:...
Uncaught ReferenceError: $ is not defined?
...
In my case I had to remove the key defer from <script src="/js/jquery-1.2.6.min.js" defer></script>
– Charden Daxicen
Mar 29 at 19:45
...