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What is the right way to check for a null string in Objective-C?
...f "null" under Cocoa/Objective C. But one further thing to note is that [title isKindOfClass:[NSNull class]] is pointlessly complex since [NSNull null] is documented to be a singleton so you can just check for pointer equality. See Topics for Cocoa: Using Null.
So a good test might be:
if (title ...
Selenium WebDriver: Wait for complex page with JavaScript to load
I have a web application to test with Selenium. There is a lot of JavaScript running on page load.
This JavaScript code is not so well written but I can't change anything.
So waiting for an element to appear in the DOM with findElement() method is not an option.
I want to create a generic func...
Statistics: combinations in Python
...al.comb (scipy.misc.comb in older versions of scipy). When exact is False, it uses the gammaln function to obtain good precision without taking much time. In the exact case it returns an arbitrary-precision integer, which might take a long time to compute.
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What does Docker add to lxc-tools (the userspace LXC tools)?
...e Docker FAQ:
Docker is not a replacement for lxc. "lxc" refers to capabilities of the linux kernel (specifically namespaces and control groups) which allow sandboxing processes from one another, and controlling their resource allocations.
On top of this low-level foundation of kernel features, Do...
How to convert date to timestamp in PHP?
... Unix and is time-zone aware, which is probably what you want if you work with dates.
If you don't care about timezone, or want to use the time zone your server uses:
$d = DateTime::createFromFormat('d-m-Y H:i:s', '22-09-2008 00:00:00');
if ($d === false) {
die("Incorrect date string");
} else...
How can I clear event subscriptions in C#?
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From within the class, you can set the (hidden) variable to null. A null reference is the canonical way of representing an empty invocation list, effectively.
From outside the class, you can't do this - events basically expose "su...
Github Windows 'Failed to sync this branch'
I am using Github Windows 1.0.38.1 and when I click the 'Sync' button after committing, I get the error
17 Answers
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How does the NSAutoreleasePool autorelease pool work?
As I understand it, anything created with an alloc , new , or copy needs to be manually released. For example:
7 Answer...
Git is ignoring files that aren't in gitignore
I have a git repository that is ignoring image files as well as a few other files, but my .gitignore file only has it ignoring a config.php file. Is there some global ignore file somewhere that I can't seem to find? I have to specify files to add them now, and it's giving me this warning:
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How to count the number of set bits in a 32-bit integer?
8 bits representing the number 7 look like this:
55 Answers
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