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Run a single migration file
...ion? I don't want to migrate to a certain version I just want to run a specific one.
11 Answers
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Prevent segue in prepareForSegue method?
...ter:
You have to implement the method
- (BOOL)shouldPerformSegueWithIdentifier:(NSString *)identifier sender:(id)sender
In your view controller. You do your validation there, and if it's OK then return YES; if it's not then return NO; and the prepareForSegue is not called.
Note that this metho...
When and why would you seal a class?
...e it really made full sense, because it becomes expensive performance-wise if left untreated. The sealed keyword tells the CLR that there is no class further down to look for methods, and that speeds things up.
In most performance-enhancing tools on the market nowadays, you will find a checkbox th...
Ignore python multiple return value
...to return the first value, x = func()[1] to return the second, and so on.
If you want to get multiple values at a time, use something like x, y = func()[2:4].
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On localhost, how do I pick a free port number?
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Do not bind to a specific port, or bind to port 0, e.g. sock.bind(('', 0)). The OS will then pick an available port for you. You can get the port that was chosen using sock.getsockname()[1], and pass it on to the slaves so that they can connect...
What's the most efficient test of whether a PHP string ends with another string?
...r_compare($str, $test, strlen($str)-strlen($test), strlen($test)) === 0;
If $test is longer than $str PHP will give a warning, so you need to check for that first.
function endswith($string, $test) {
$strlen = strlen($string);
$testlen = strlen($test);
if ($testlen > $strlen) retur...
How to grab substring before a specified character jQuery or JavaScript
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This will not work if the string being searched does not contain an instance of the search character. It will return an empty string.
– David G
Aug 20 '15 at 19:48
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Do python projects need a MANIFEST.in, and what should be in it?
...d) tells me to include doc/txt files and .py files are excluded in MANIFEST.in file
2 Answers
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What is the Oracle equivalent of SQL Server's IsNull() function?
In SQL Server we can type IsNull() to determine if a field is null. Is there an equivalent function in PL/SQL?
4 Answers...
How to join NSArray elements into an NSString?
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There's also this variant, if your original array contains Key-Value objects from which you only want to pick one property (that can be serialized as a string ):
@implementation NSArray (itertools)
-(NSMutableString *)stringByJoiningOnProperty:(NSSt...