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When should I use nil and NULL in Objective-C?
...e object. Let's have an example:
NSMutableArray *check = [[NSMutableArray alloc] init];
[check addObject:[NSNull null]];
[check addObject:nil];
On the second line, we will not get any error, because it is perfectly fair to insert a NSNull object into a collection type object. On the third line, w...
Maximum size of an Array in Javascript
...a big deal
x=3e7 takes 1300ms, which is pretty bad
x=4e7 takes 11000ms and allocates an extra 2.5GB of memory
So around 30 million elements is a hard upper limit, because the javascript VM falls off a cliff at 40 million elements and will probably crash the process.
...
Is it possible to get all arguments of a function as single object inside that function?
...uments); cant be the best way because it causes an unnecessary empty array allocation.
– Thomas Eding
Jun 22 '17 at 16:49
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Generate a random alphanumeric string in Cocoa
... genRandStringLength should just return randomString. There's no reason to alloc and init (and not autorelease!) a whole new string.
– kevingessner
Apr 14 '10 at 0:49
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Why (0-6) is -6 = False? [duplicate]
... is an array of 262 pointers to integer objects. Those integer objects are allocated during initialization in a block of integer objects we saw above. The small integers range is from -5 to 256. Many Python programs spend a lot of time using integers in that range so this is a smart decision.
This...
Zero-based month numbering [closed]
... pointer arithmetics where you would use one base pointer pointing at some allocated memory, plus a second pointer which would be at an offset from this base pointer. Here, using the value zero makes a lot of sense to point the offset to the base of the memory block. (General array logic tends to be...
How to sort in mongoose?
...e query.
The Model.find() implementation (at this version) does a sliding allocation of properties to handle optional params (which is what confused me!):
Model.find = function find (conditions, fields, options, callback) {
if ('function' == typeof conditions) {
callback = conditions;
co...
Best practice: PHP Magic Methods __set and __get [duplicate]
...e you have $user->getName() (returns private property) and $user->getToken($key) (computed). The day your getter gets more than a getter and needs to do some logic, everything is still consistent.
Finally, and this is the biggest problem IMO : this is magic. And magic is very very bad, becau...
PHP Regex to check date is in YYYY-MM-DD format
...tice under any circumstances. Here's how:
explode is limited to return 3 tokens (so that if the input is "1-2-3-4", $d will become "3-4")
ctype_digit is used to make sure that the input does not contain any non-numeric characters (apart from the dashes)
array_pad is used (with a default value that...
Load and execute external js file in node.js with access to local variables?
...L scope that's always a bad thing to do, instead you can use the 'exports' token, like this:
// circle.js
var PI = 3.14; // PI will not be accessible from outside this module
exports.area = function (r) {
return PI * r * r;
};
exports.circumference = function (r) {
return 2 * PI * r;
};
An...