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How to return result of a SELECT inside a function in PostgreSQL?
... -- potential ambiguity
END
$func$ LANGUAGE plpgsql;
Call:
SELECT * FROM word_frequency(123);
Explanation:
It is much more practical to explicitly define the return type than simply declaring it as record. This way you don't have to provide a column definition list with eve...
What exactly are late static bindings in PHP?
...s in the PHP manual. However, I'll try to give you a quick summary.
Basically, it boils down to the fact that the self keyword does not follow the same rules of inheritance. self always resolves to the class in which it is used. This means that if you make a method in a parent class and call it ...
How does zip(*[iter(s)]*n) work in Python?
... each element is x. *arg unpacks a sequence into arguments for a function call. Therefore you're passing the same iterator 3 times to zip(), and it pulls an item from the iterator each time.
x = iter([1,2,3,4,5,6,7,8,9])
print zip(x, x, x)
...
How to refer to relative paths of resources when working with a code repository
...Try to use a filename relative to the current files path. Example for './my_file':
fn = os.path.join(os.path.dirname(__file__), 'my_file')
In Python 3.4+ you can also use pathlib:
fn = pathlib.Path(__file__).parent / 'my_file'
...
How to resolve “must be an instance of string, string given” prior to PHP 7?
... supposed to work to begin with. Given the dynamic typing system, this actually makes some sort of perverted sense.
You can only manually "type hint" scalar types:
function foo($string) {
if (!is_string($string)) {
trigger_error('No, you fool!');
return;
}
...
}
...
Regex for password must contain at least eight characters, at least one number and both lower and up
...
"^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,}$" does not allow symbols as one of the 8 characters
– Wee
Jan 6 '15 at 2:30
2
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How to detect iPhone 5 (widescreen devices)?
...
First of all, you shouldn't rebuild all your views to fit a new screen, nor use different views for different screen sizes.
Use the auto-resizing capabilities of iOS, so your views can adjust, and adapt any screen size.
That's not v...
What is the function __construct used for?
I have been noticing __construct a lot with classes. I did a little reading and surfing the web, but I couldn't find an explanation I could understand. I am just beginning with OOP.
...
How to see which flags -march=native will activate?
I'm compiling my C++ app using GCC 4.3. Instead of manually selecting the optimization flags I'm using -march=native , which in theory should add all optimization flags applicable to the hardware I'm compiling on. But how can I check which flags is it actually using?
...
Convert JavaScript string in dot notation into an object reference
...k themselves the question "why am I doing this?"
It is of course generally fine to do this if your use case is small and you will not run into performance issues, AND you won't need to build upon your abstraction to make it more complicated later. In fact, if this will reduce code complexity an...