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How to perform Callbacks in Objective-C
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Ryan BrodieRyan Brodie
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WHERE vs HAVING
... general, you can reference aliases in neither of these clauses, but MySQL allows referencing SELECT level aliases in GROUP BY, ORDER BY and HAVING.
And are there any downsides instead of doing "WHERE 1" (writing the whole definition instead of a column name)
If your calculated expression does...
PHP Regex to check date is in YYYY-MM-DD format
...ing to be more fuss -- and February 29 cannot be validated with a regex at all.
The drawback of this approach is that you have to be very careful to reject all possible "bad" inputs while not emitting a notice under any circumstances. Here's how:
explode is limited to return 3 tokens (so that if ...
How to call asynchronous method from synchronous method in C#?
I have a public async void Foo() method that I want to call from synchronous method. So far all I have seen from MSDN documentation is calling async methods via async methods, but my whole program is not built with async methods.
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Saving image from PHP URL
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If you have allow_url_fopen set to true:
$url = 'http://example.com/image.php';
$img = '/my/folder/flower.gif';
file_put_contents($img, file_get_contents($url));
Else use cURL:
$ch = curl_init('http://example.com/image.php');
$fp = f...
How do I create a constant in Python?
.... This is the closest equivalent to Java's final. However, it does not actually prevent reassignment:
from typing import Final
a: Final = 1
# Executes fine, but mypy will report an error if you run mypy on this:
a = 2
sha...
How to remove folders with a certain name
...t this, find will still try to visit the now missing folder and will eventually exit with an error code, which can e.g. fail a Docker build.
– Czyzby
Mar 18 at 13:19
add a com...
The tilde operator in Python
...a unary operator (taking a single argument) that is borrowed from C, where all data types are just different ways of interpreting bytes. It is the "invert" or "complement" operation, in which all the bits of the input data are reversed.
In Python, for integers, the bits of the twos-complement repr...
How to tell if a string contains a certain character in JavaScript?
...tion does. There are a lot of people who don't understand regex, and generally the simpler answer is the best.
– kemiller2002
Oct 13 '15 at 19:19
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C++ mark as deprecated
...erface that I want to deprecate with portable C++.
When I Googled for this all I got was a Microsoft specific solution; #pragma deprecated and __declspec(deprecated) .
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