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How to declare a global variable in JavaScript?
...e is a live example for you: http://jsfiddle.net/fxCE9/
var myVariable = 'Hello';
alert('value: ' + myVariable);
myFunction1();
alert('value: ' + myVariable);
myFunction2();
alert('value: ' + myVariable);
function myFunction1() {
myVariable = 'Hello 1';
}
function myFunction2() {
myVaria...
Are JavaScript strings immutable? Do I need a “string builder” in JavaScript?
...s to the same string, modifying one doesn't affect the other
let a = b = "hello";
a = a + " world";
// b is not affected
However, I've always heard what Ash mentioned in his answer (that using Array.join is faster for concatenation) so I wanted to test out the different methods of concatenating s...
Run R script from command line
... add an appropriate #! to the top of the script
#!/usr/bin/env Rscript
sayHello <- function(){
print('hello')
}
sayHello()
I will also note that if you're running on a *unix system there is the useful littler package which provides easy command line piping to R. It may be necessary to use ...
Get users by name property using Firebase
...ds.firebaseio.com/users');
var myUser = usersRef.child(escapeEmailAddress('hello@hello.com'))
myUser.set({ email: 'hello@hello.com', name: 'Alex', phone: 12912912 });
Note that since Firebase does not permit certain characters in references (see Creating References), we remove the . and replace i...
Best Practices: working with long, multiline strings in PHP?
...g. So I might do something like this with your original example:
$text = 'Hello ' . $vars->name . ','
. "\r\n\r\n"
. 'The second line starts two lines below.'
. "\r\n\r\n"
. 'I also don\'t want any spaces before the new line,'
. ' so it\'s butted up against the left...
Windows recursive grep command-line
...h strings unless the argument is prefixed
with /C. For example, 'FINDSTR "hello there" x.y' searches for "hello" or
"there" in file x.y. 'FINDSTR /C:"hello there" x.y' searches for
"hello there" in file x.y.
Regular expression quick reference:
. Wildcard: any character
* Repeat:...
What does a tilde do when it precedes an expression?
...of presence/absence of a substring in another string in this way
var a = "Hello Baby";
if (a.indexOf("Ba") >= 0) {
// found it
}
if (a.indexOf("Ba") != -1) {
// found it
}
if (a.indexOf("aB") < 0) {
// not found
}
if (a.indexOf( "aB" ) == -1) {
// not found
}
However, i...
Remove all child elements of a DOM node in JavaScript
..."height: 100px; width: 100px; border: 1px solid black;">
<span>Hello</span>
</div>
<button id='doFoo'>Remove via innerHTML</button>
Option 1 B: Clearing textContent
As above, but use .textContent. According to MDN this will be faster than innerHTML as b...
How can I count the number of matches for a regex?
...
class Test {
public static void main(String[] args) {
String hello = "HelloxxxHelloxxxHello";
Pattern pattern = Pattern.compile("Hello");
Matcher matcher = pattern.matcher(hello);
int count = 0;
while (matcher.find())
count++;
Syste...
Is there a WebSocket client implemented for Python? [closed]
...on
ws = create_connection("ws://localhost:8080/websocket")
print "Sending 'Hello, World'..."
ws.send("Hello, World")
print "Sent"
print "Receiving..."
result = ws.recv()
print "Received '%s'" % result
ws.close()
Sample server code:
#!/usr/bin/python
import websocket
import thread
import time
de...