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Why sizeof int is wrong, while sizeof(int) is right?
...e such example of where you might want to use it on an expression:
sizeof array / sizeof array[0]
However, for the sake of consistency, and to avoid bugs related to operator precedence, I would personally advise to always use () no matter the situation.
...
What is the best regular expression to check if a string is a valid URL?
..._encoded = '%' . cc($HEXDIG) . cc($HEXDIG);
$dec_octet = ncg(implode('|', array(
cc($DIGIT),
cc('1-9') . cc($DIGIT),
'1' . cc($DIGIT) . cc($DIGIT),
'2' . cc('0-4') . cc($DIGIT),
'25' . cc('0-5')
)));
$IPv4address = $dec_octet . ncg('\\.' . $dec_octet, '{3}');
$h16 = cc($HEXDIG...
Quick Way to Implement Dictionary in C
...For ease of implementation, it's hard to beat naively searching through an array. Aside from some error checking, this is a complete implementation (untested).
typedef struct dict_entry_s {
const char *key;
int value;
} dict_entry_s;
typedef struct dict_s {
int len;
int cap;
di...
Choice between vector::resize() and vector::reserve()
...ut that's the only effect.
So it depends on what you want. If you want an array of 1000 default items, use resize(). If you want an array to which you expect to insert 1000 items and want to avoid a couple of allocations, use reserve().
EDIT: Blastfurnace's comment made me read the question again ...
Why does Python code use len() function instead of a length method?
...n and must work efficiently for such basic and diverse types as str, list, array.array etc.
However, to promote consistency, when applying len(o) to a user-defined type, Python calls o.__len__() as a fallback. __len__, __abs__ and all the other special methods documented in the Python Data Model ...
Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
...
Yes, there is a difference. These are legal:
h = { :$in => array }
h = { :'a.b' => 'c' }
h[:s] = 42
but these are not:
h = { $in: array }
h = { 'a.b': 'c' } # but this is okay in Ruby2.2+
h[s:] = 42
You can also use anything as a key with => so you can do this:
h = { C.ne...
In Python, when to use a Dictionary, List or Set?
...to incorporate the following data structures into the diagram: bytes, byte arrays, tuples, named_tuples, ChainMap, Counter, and arrays.
OrderedDict and deque are available via collections module.
heapq is available from the heapq module
LifoQueue, Queue, and PriorityQueue are available via the que...
jquery get all form elements: input, textarea & select
...
If you have additional types, edit the selector:
var formElements = new Array();
$("form :input").each(function(){
formElements.push($(this));
});
All form elements are now in the array formElements.
share
...
How can I merge properties of two JavaScript objects dynamically?
...
Also, obj2[p].constructor == Array is needed in any case where there is an array of objects.
– The Composer
Dec 15 '15 at 19:27
...
How to instantiate a File object in JavaScript?
...w File([""], "filename");
The first argument is the data provided as an array of lines of text;
The second argument is the filename ;
The third argument looks like:
var f = new File([""], "filename.txt", {type: "text/plain", lastModified: date})
It works in FireFox, Chrome and Opera, but not ...