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What are Unwind segues for and how do you use them?
...e want to unwind to Red from Green when the button is pressed:
You must select the action which is defined in the view controller you want to unwind to:
You can also unwind to Red from Blue (which is "two steps away" in the navigation stack). The key is selecting the correct unwind action.
Be...
What is the best way to use a HashMap in C++?
...gt;
#include <iostream>
#include <cassert>
int main(int argc, char **argv)
{
std::map<std::string, int> m;
m["hello"] = 23;
// check if key is present
if (m.find("world") != m.end())
std::cout << "map contains key world!\n";
// retrieve
std::cout << m["...
Linux: compute a single hash for a given folder & contents?
...
@RichardBronosky - Let us assume we have two files, A and B. A contains "foo" and B contains "bar was here". With your method, we would not be able to separate that from two files C and D, where C contains "foobar" and D contain...
How do you copy and paste into Git Bash
...
With QuickEdit on this becomes pretty easy: select, Enter, Insert
– gphilip
Feb 10 '14 at 8:49
3
...
How to select only the records with the highest date in LINQ
...is:
var q = from n in table
group n by n.AccountId into g
select new {AccountId = g.Key, Date = g.Max(t=>t.Date)};
If you want the whole record:
var q = from n in table
group n by n.AccountId into g
select g.OrderByDescending(t=>t.Date).FirstOrDefault();
...
Determine device (iPhone, iPod Touch) with iOS
..._t size;
sysctlbyname("hw.machine", NULL, &size, NULL, 0);
char *machine = malloc(size);
sysctlbyname("hw.machine", machine, &size, NULL, 0);
NSString *platform = [NSString stringWithCString:machine encoding:NSUTF8StringEncoding];
free(machine);
if ([platf...
Python in Xcode 4+?
...
In the menu bar, click “File” → “New” → “New Project…”.
Select “Other” in the left pane, then "External Build System" in the right page, and next click "Next".
Enter the product name, organization name, or organization identifier.
For the “Build Tool” field, type in /usr/l...
Null coalescing in powershell
...ll values in the same order as the array created in Step 1.
[0] is used to select the first element of the filtered array.
Simplifying that:
Create an array of possible values, in preferred order
Exclude all null values from the array
Take the first item from the resulting array
Caveats
Unlik...
Using boolean values in C
...
Why use int for bool? That's wasteful. Use unsigned char. Or use C's builtin _Bool.
– user12211554
May 19 at 21:30
...
PostgreSQL Autoincrement
...RT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not alter SERIAL onto an existing column.
sha...