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To ARC or not to ARC? What are the pros and cons? [closed]
...like it can unroll loops, eliminate temporary variables, inline functions, etc.)
OK, now I will tell you about the small downsides:
If you're a long-time ObjC developer, you will twitch for about a week when you see ARC code. You will very quickly get over this.
There are some (very) small compli...
How to check if a variable is a dictionary in Python?
...egin with ('god object's, overriding standard library/language constructs, etc.) The original question is itself an XY problem. Why does the OP need to check type? Because according to their code what they really want to do is to check whether an item in their collection behaves like a collection (i...
Why do we need virtual functions in C++?
...- obviously wrapping the variable declaration and calls in a main function etc. Pointer-to-derived implicitly casts to pointer-to-base (more specialized implicitly casts to more general). Visa-versa you need an explicit cast, usually a dynamic_cast. Anything else - very prone to undefined behavior s...
How does the Java 'for each' loop work?
...nges to the test-function (int[] to List<Integer>, length to size(), etc.):
[C:\java_code\]java TimeIteratorVsIndexIntegerList 1000000
Test A: 3,429,929,976 nanoseconds
Test B: 5,262,782,488 nanoseconds
A faster by 1,832,852,512 nanoseconds (34.326681820485675% faster)
[C:\java_code\]java Ti...
deciding among subprocess, multiprocessing, and thread in Python?
...multiprocessing model gives each process its own memory, file descriptors, etc. A crash or unhandled exception in any one of them will only kill that resource and robustly handling the disappearance of a child or sibling process can be considerably easier than debugging, isolating and fixing or wor...
Regular cast vs. static_cast vs. dynamic_cast [duplicate]
...d to cast between
the integer types. 'e.g.' char->long, int->short etc.
Static cast is also used to cast pointers to related types, for
example casting void* to the appropriate type.
dynamic_cast
Dynamic cast is used to convert pointers and references at run-time,
generall...
Where in a virtualenv does the custom code go?
...it away and recreate it anytime, or create a new one on a new deploy host, etc.
Many people in fact use virtualenvwrapper, which removes the actual virtualenvs from your awareness almost completely, placing them all side-by-side in $HOME/.virtualenvs by default.
...
How to encrypt/decrypt data in php?
...n substr($data, 0, -ord($data[strlen($data) - 1]));
}
$row = $result->fetch(PDO::FETCH_ASSOC); // read from database result
// $enc_name = base64_decode($row['Name']);
// $enc_name = hex2bin($row['Name']);
$enc_name = $row['Name'];
// $iv = base64_decode($row['IV']);
// $iv = hex2bin($row['IV'])...
Does JavaScript have the interface type (such as Java's 'interface')?
...-oriented language. All the crap required to emulate classes, interfaces, etc... that is what'll really make your brain hurt. Prototypes? Simple stuff, really, once you stop fighting them.
– cHao
Aug 21 '14 at 14:21
...
Jelly Bean DatePickerDialog — is there a way to cancel?
...,
null, // instead of a listener
2012, 6, 15);
picker.setCancelable(true);
picker.setCanceledOnTouchOutside(true);
picker.setButton(DialogInterface.BUTTON_POSITIVE, "OK",
new DialogInterface.OnClickListener() {
@Override
public void onClick...