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How to check if element has any children in Javascript?
...log(
isEmpty("#one"), // false
isEmpty("#two"), // true
isEmpty(".foo"), // false
isEmpty(".bar") // true
);
<div id="one">
foo
</div>
<div id="two">
</div>
<div class="foo"></div>
<div class="foo"><p>foo</p></div&...
How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?
...
You would do it like this:
std::string prefix("--foo=");
if (!arg.compare(0, prefix.size(), prefix))
foo_value = atoi(arg.substr(prefix.size()).c_str());
Looking for a lib such as Boost.ProgramOptions that does this for you is also a good idea.
...
Python function global variables?
...nc_B calls func_A. In this example, order does matter:
def a():
global foo
foo = 'A'
def b():
global foo
foo = 'B'
b()
a()
print foo
# prints 'A' because a() was the last function to modify 'foo'.
Note that global is only required to modify global objects. You can still access them fr...
Running shell command and capturing the output
...nt:
>>> cmd = ['awk', 'length($0) > 5']
>>> input = 'foo\nfoofoo\n'.encode('utf-8')
>>> result = subprocess.run(cmd, stdout=subprocess.PIPE, input=input)
>>> result.stdout.decode('utf-8')
'foofoo\n'
You can capture errors by passing stderr=subprocess.PIPE (c...
How do I grab an INI value within a shell script?
...tr -d ' ')
To support ; comments, replace them with #:
$ sed "s/;/#/g" foo.ini | source /dev/stdin
The sections aren't supported (e.g. if you've [section-name], then you've to filter it out as shown above, e.g. grep =), the same for other unexpected errors.
If you need to read specific value u...
What does “=>” mean in PHP?
...Note that this can be used for numerically indexed arrays too.
Example:
$foo = array('car', 'truck', 'van', 'bike', 'rickshaw');
foreach ($foo as $i => $type) {
echo "{$i}: {$type}\n";
}
// prints:
// 0: car
// 1: truck
// 2: van
// 3: bike
// 4: rickshaw
...
How can I get the behavior of GNU's readlink -f on a Mac?
...can tell, that won't work if a parent dir of the path is a symlink. Eg. if foo -> /var/cux, then foo/bar won't be resolved, because bar isn't a link, although foo is.
– troelskn
Jul 12 '09 at 23:36
...
Java Reflection: How to get the name of a variable?
...hich I wouldn't use - see below):
public void printFieldNames(Object obj, Foo... foos) {
List<Foo> fooList = Arrays.asList(foos);
for(Field field : obj.getClass().getFields()) {
if(fooList.contains(field.get()) {
System.out.println(field.getName());
}
...
How to use Swift @autoclosure
...look at example
func testClosures() {
//closures
XCTAssertEqual("fooWithClosure0 foo0", fooWithClosure0(p: foo0))
XCTAssertEqual("fooWithClosure1 foo1 1", fooWithClosure1(p: foo1))
XCTAssertEqual("fooWithClosure2 foo2 3", fooWithClosure2(p: foo2))
XCTAssertEqual("fooWithClosur...
http to https apache redirection
...he VirtualHost file. It is the recommended method.
– foochow
Sep 25 '13 at 23:54
4
After changing...