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The new syntax “= default” in C++11
...ct in the memory started from address of variable x (instead of new memory allocation). This syntax is used to create object at pre-allocated memory. As in our case the size of B = the size of int, so new(&x)A() will create new object in the place of x variable.
– Slavenski...
Why is __init__() always called after __new__()?
...ost well-known OO languages, an expression like SomeClass(arg1, arg2) will allocate a new instance, initialise the instance's attributes, and then return it.
In most well-known OO languages, the "initialise the instance's attributes" part can be customised for each class by defining a constructor, ...
Why isn't std::initializer_list a language built-in?
... @elmes: Actually it is more like std::array. But std::array allocates memory while std::initializaer_list wraps a compile-time array. Think of it as the difference between char s[] = "array"; and char *s = "initializer_list";.
– rodrigo
Mar 4 '13...
Vertically align text to top within a UILabel
...abelFrame = CGRectMake(20, 20, 280, 150);
UILabel *myLabel = [[UILabel alloc] initWithFrame:labelFrame];
[myLabel setBackgroundColor:[UIColor orangeColor]];
NSString *labelText = @"I am the very model of a modern Major-General, I've information vegetable, animal, and mineral";
[myLa...
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.
...
Red black tree over avl tree
...
Programmers generally don't like to dynamically allocate memory.
The problem with the avl tree is that for "n" elements you need atleast log2(log2(n))...(height->log2(n)) bits to store the height of the tree!
So when you are handling enormous data you cannot be sure of ...
How to use PHP OPCache?
...econds) to check file timestamps for changes to the shared
;memory storage allocation.
opcache.revalidate_freq=60
;If enabled, a fast shutdown sequence is used for the accelerated code
;The fast shutdown sequence doesn't free each allocated block, but lets
;the Zend Engine Memory Manager do the wor...
How to change UIPickerView height
... desired frame size at creation time, e.g:
smallerPicker = [[UIPickerView alloc] initWithFrame:CGRectMake(0.0, 0.0, 320.0, 120.0)];
You will discover that at various heights and widths, there are visual glitches. Obviously, these glitches would either need to be worked around somehow, or choose an...
Is String.Format as efficient as StringBuilder
...eration for a String or StringBuilder object depends on how often a memory allocation occurs. A String concatenation operation always allocates memory, whereas a StringBuilder concatenation operation only allocates memory if the StringBuilder object buffer is too small to accommodate the new data. C...
Why is @autoreleasepool still needed with ARC?
...now there's a ton of objects ready to be cleared out, you have a loop that allocates a bunch of temp objects, so you "know" (or Instruments might tell you :) that adding a release pool around the loop would be a good idea.
– Graham Perks
Jan 31 '12 at 21:28
...