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When should I use nil and NULL in Objective-C?
...ntions this, but if you dig into objc.h, you'll find the line #define nill __DARWIN_NULL.
– gkb0986
Oct 25 '13 at 3:12
1
...
How to lock orientation during runtime
...
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
Called on an activity, will lock it to landscape. Look for the other flags in the ActivityInfo class. You can lock it back to portrait or make it sensor/slider driven.
More info here: http://www....
Segue to another storyboard?
...gue is an abstract class. You need to subclass it and implement perform in order for it to do anything. They're really meant to be created in storyboards. You can push the view controller manually, though, which is a good solution. lnafziger's answer does this well:
UIStoryboard *secondStoryBoard =...
Find which version of package is installed with pip
...hat is the difference between using pip list and doing import X and then X.__version__? Are both the package versions?
– variable
Oct 13 '19 at 4:27
...
How to initialize a private static const map in C++?
...ap>
using namespace std;
struct A{
static map<int,int> create_map()
{
map<int,int> m;
m[1] = 2;
m[3] = 4;
m[5] = 6;
return m;
}
static const map<int,int> myMap;
};
const map<int,int> A:: myMap = ...
How do I perform the SQL Join equivalent in MongoDB?
...ttps://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <field from the input documents>,
foreignField: <field from the documents of the "from" collection>...
How do I print the elements of a C++ vector in GDB?
...td::vector<int> called myVector, do the following:
print *(myVector._M_impl._M_start)@myVector.size()
To print only the first N elements, do:
print *(myVector._M_impl._M_start)@N
Explanation
This is probably heavily dependent on your compiler version, but for GCC 4.1.2, the pointer to t...
How to check if a python module exists without importing it
...mport can find something in python2, using imp
import imp
try:
imp.find_module('eggs')
found = True
except ImportError:
found = False
To find dotted imports, you need to do more:
import imp
try:
spam_info = imp.find_module('spam')
spam = imp.load_module('spam', *spam_info)
i...
Is there a foreach loop in Go?
...
https://golang.org/ref/spec#For_range
A "for" statement with a "range" clause iterates through all entries
of an array, slice, string or map, or values received on a channel.
For each entry it assigns iteration values to corresponding iteration
v...
Purpose of memory alignment
... have the vastly smaller width of the cache line size. This will be on the order of 128 bits.
So:
262,144 bits - size of memory
128 bits - size of bus
Misaligned accesses will occasionally overlap two cache lines, and this will require an entirely new cache read in order to obtain the data. ...