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Deleting array elements in JavaScript - delete vs splice
... myArray = ['a', 'b', 'c', 'd']
["a", "b", "c", "d"]
> delete myArray[0]
true
> myArray[0]
undefined
Note that it is not in fact set to the value undefined, rather the property is removed from the array, making it appear undefined. The Chrome dev tools make this distinction clear by pr...
What is the !! (not not) operator in JavaScript?
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Converts Object to boolean. If it was falsey (e.g. 0, null, undefined, etc.), it will be false, otherwise, true.
!oObject // inverted boolean
!!oObject // non inverted boolean so true boolean representation
So !! is not an operator, it's just the ! operator twice.
Real W...
How to use chrome web inspector to view hover code
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answered Jul 21 '11 at 15:30
Travis NorthcuttTravis Northcutt
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compilation warning: no rule to process file for architecture i386
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30
Because this is the list of source files that will be compiled, and normally you have already included <file>.h inside your <file&g...
Get file size, image width and height before upload
... sources will be a URL representing the Blob object
<img src="blob:null/026cceb9-edr4-4281-babb-b56cbf759a3d">
const EL_browse = document.getElementById('browse');
const EL_preview = document.getElementById('preview');
const readImage = file => {
if ( !(/^image\/(png|jpe?g|gif...
What is http multipart request?
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IggyIggy
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Should I delete the cgi-bin folder in a subdomain I just created?
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answered Feb 23 '10 at 20:56
janmoesenjanmoesen
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What's the difference of strings within single or double quotes in groovy?
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edited May 23 '17 at 10:31
Community♦
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answered Jul 20 '11 at 12:03
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MongoDB/Mongoose querying at a specific date?
...osts.find( //query today up to tonight
{"created_on": {"$gte": new Date(2012, 7, 14), "$lt": new Date(2012, 7, 15)}})
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Set the selected index of a Dropdown using jQuery
...uery
// sets selected index of a select box to the option with the value "0"
$("select#elem").val('0');
// sets selected index of a select box to the option with the value ""
$("select#elem").val('');
// sets selected index to first item using the DOM
$("select#elem")[0].selectedIndex = 0;
// ...