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capturing self strongly in this block is likely to lead to a retain cycle
...ng a weak reference to self before accessing timerDisp inside your block:
__weak typeof(self) weakSelf = self;
[player addPeriodicTimeObserverForInterval:CMTimeMakeWithSeconds(0.1, 100)
queue:nil
usingBlock:^(CMTime time) {
...
How can I represent an 'Enum' in Python?
...34. Code is not perfectly compatible between py2 and py3, e.g. you'll need __order__ in python 2).
To use enum34, do $ pip install enum34
To use aenum, do $ pip install aenum
Installing enum (no numbers) will install a completely different and incompatible version.
from enum import Enum #...
From an array of objects, extract value of a property as array
...
Check out Lodash's _.pluck() function or Underscore's _.pluck() function. Both do exactly what you want in a single function call!
var result = _.pluck(objArray, 'foo');
Update: _.pluck() has been removed as of Lodash v4.0.0, in favour of _...
Python __str__ and lists
...
Calling string on a python list calls the __repr__ method on each element inside. For some items, __str__ and __repr__ are the same. If you want that behavior, do:
def __str__(self):
...
def __repr__(self):
return self.__str__()
...
Unmangling the result of std::type_info::name
... calling function. This should be relatively easy, standard C++ has a type_info class. This contains the name of the typeid'd class/function/etc. but it's mangled. It's not very useful. I.e. typeid(std::vector<int>).name() returns St6vectorIiSaIiEE .
...
How to mock an import
...importing A to get what you want:
test.py:
import sys
sys.modules['B'] = __import__('mock_B')
import A
print(A.B.__name__)
A.py:
import B
Note B.py does not exist, but when running test.py no error is returned and print(A.B.__name__) prints mock_B. You still have to create a mock_B.py where ...
Why aren't variables declared in “try” in scope in “catch” or “finally”?
...Reader sr,
[1] class [mscorlib]System.Exception ex)
IL_0000: ldnull
IL_0001: stloc.0
.try
{
.try
{
IL_0002: ldsfld string UsingTest.Class1::path
IL_0007: newobj instance void [mscorlib]System.IO.StreamReader::.cto...
Odd behavior when Java converts int to byte?
...
132 in digits (base 10) is 1000_0100 in bits (base 2) and Java stores int in 32 bits:
0000_0000_0000_0000_0000_0000_1000_0100
Algorithm for int-to-byte is left-truncate; Algorithm for System.out.println is two's-complement (Two's-complement is if leftmos...
Weighted random numbers
...er is less than that item's weight
Pseudo-code illustrating this:
int sum_of_weight = 0;
for(int i=0; i<num_choices; i++) {
sum_of_weight += choice_weight[i];
}
int rnd = random(sum_of_weight);
for(int i=0; i<num_choices; i++) {
if(rnd < choice_weight[i])
return i;
rnd -= choic...
Code Golf: Lasers
...amp;!ge,$s=$r+=99for<>;%d='>.^1<2v3'=~/./g;($r)=grep$d|=$d{$t{$_}},%t;
{$_=$t{$r+=(1,-99,-1,99)[$d^=3*/\\/+m</>]};/[\/\\ ]/&&redo}die/x/?true:false,$/
The first line loads the input into %t, a table of the board where $t{99*i+j} holds the character at row i,column j. Then...