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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&...
Getter and Setter?
...y is of a specific type without using setters.
In PHP, this works:
class Foo {
public $bar; // should be an integer
}
$foo = new Foo;
$foo->bar = "string";
In Java, it doesn't:
class Foo {
public int bar;
}
Foo myFoo = new Foo();
myFoo.bar = "string"; // error
Using magic methods (__...
Check if object exists in JavaScript
...null !== undefined gives you what you might expect. Please also note, that foo != null can be an effective way to check if a variable is neither undefined nor null. Of course you can be explicit, because it may help readability.
If you restrict the question to check if an object exists, typeof o ==...
count (non-blank) lines-of-code in bash
...
cat foo.c | sed '/^\s*$/d' | wc -l
And if you consider comments blank lines:
cat foo.pl | sed '/^\s*#/d;/^\s*$/d' | wc -l
Although, that's language dependent.
...
Understanding events and event handlers in C#
... return void and take a string.
public delegate void MyEventHandler(string foo);
//This event can cause any method which conforms
//to MyEventHandler to be called.
public event MyEventHandler SomethingHappened;
//Here is some code I want to be executed
//when SomethingHappened fires.
void HandleSo...
Turn off constraints temporarily (MS SQL)
...e FK and CHECK constraints only in SQL 2005+. See ALTER TABLE
ALTER TABLE foo NOCHECK CONSTRAINT ALL
or
ALTER TABLE foo NOCHECK CONSTRAINT CK_foo_column
Primary keys and unique constraints can not be disabled, but this should be OK if I've understood you correctly.
...
Zip lists in Python
...tion!
1. Build a dictionary [2] out of two lists
keys = ["drink","band","food"]
values = ["La Croix", "Daft Punk", "Sushi"]
my_favorite = dict( zip(keys, values) )
my_favorite["drink"]
# 'La Croix'
my_faves = dict()
for i in range(len(keys)):
my_faves[keys[i]] = values[i]
zip is an elega...
HTML5 Local Storage fallback solutions [closed]
...ttp://jsfiddle.net/aamir/S4X35/
HTML:
<a href='#' onclick="store.set('foo','bar')">set key: foo, with value: bar</a><br/>
<a href='#' onclick="alert(store.get('foo'))">get key: foo</a><br/>
<a href='#' onclick="store.del('foo')">delete key: foo</a>...
What does $$ (dollar dollar or double dollar) mean in PHP?
... resolves a variable by that string.
So, consider this example
$inner = "foo";
$outer = "inner";
The variable:
$$outer
would equal the string "foo"
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What does the slash mean in help() output?
...hen his proposal won.
Heh. If that's true, my '/' proposal wins:
def foo(pos_only, /, pos_or_kw, *, kw_only): ...
I think the very relevant document covering this is PEP 570.
Where recap section looks nice.
Recap
The use case will determine which parameters to use in the function...