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How to Deep clone in javascript
...first, a code example which clones object literals, any primitives, arrays and DOM nodes.
function clone(item) {
if (!item) { return item; } // null, undefined values check
var types = [ Number, String, Boolean ],
result;
// normalizing primitives if someone did new String('a...
When should I use cross apply over inner join?
...NER JOIN condition.
You could probably do something like that using CTE's and window function:
WITH t2o AS
(
SELECT t2.*, ROW_NUMBER() OVER (PARTITION BY t1_id ORDER BY rank) AS rn
FROM t2
)
SELECT t1.*, t2o.*
FROM t1
INNER JOIN
t2o
ON t2o.t1...
What is the difference between Caching and Memoization?
I would like to know what the actual difference between caching and memoization is.
As I see it, both involve avoiding repeated function calls to get data by storing it .
...
What is the difference between String.slice and String.substring?
...xactly like substr() in Firefox. This behavior is observed in both Firefox and IE.
If stop is negative: sets stop to: string.length – Math.abs(stop) (original value), except bounded at 0 (thus, Math.max(0, string.length + stop)) as covered in the ECMA specification.
Source: Rudimentary Art of Pr...
Can I Replace Apache with Node.js?
... have a website running on CentOS using the usual suspects (Apache, MySQL, and PHP). Since the time this website was originally launched, it has evolved quite a bit and now I'd like to do fancier things with it—namely real-time notifications. From what I've read, Apache handles this poorly. I'm wo...
ng-repeat :filter by single field
I have an array of products that I'm repeating over using ng-repeat and am using
12 Answers
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When is null or undefined used in JavaScript? [duplicate]
...e DOM methods getElementById(), nextSibling(), childNodes[n], parentNode() and so on return null (defined but having no value) when the call does not return a node object.
The property is defined, but the object it refers to does not exist.
This is one of the few times you may not want to test fo...
Why would I make() or new()?
...ents dedicate many paragraphs to explaining the difference between new() and make() , but in practice, you can create objects within local scope and return them.
...
Best way to initialize (empty) array in PHP
...o = [] rather than var foo = new Array() for reasons of object creation and instantiation. I wonder whether there are any equivalences in PHP?
...
Which regular expression operator means 'Don't' match this character?
...rs.
Instead of specifying all the characters literally, you can use shorthands inside character classes: [\w] (lowercase) will match any "word character" (letter, numbers and underscore), [\W] (uppercase) will match anything but word characters; similarly, [\d] will match the 0-9 digits while [\D]...