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What do the plus and minus signs mean in Objective-C next to a method?
...in Objective C is like this:
NSNumber *myNumber = [NSNumber numberWithInt:123];
which is calling the 'numberWithInt' class method of the NSNumber class, which is a 'factory' method (i.e. a method that provides you with a 'ready made instance' of an object).
Objective C also allows the creation o...
Select by partial string from a pandas DataFrame
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df[df['value'].astype(str).str.contains('1234.+')] for filtering out non-string-type columns.
– François Leblanc
Feb 13 '18 at 20:22
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How do you clear a slice in Go?
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123
It all depends on what is your definition of 'clear'. One of the valid ones certainly is:
sli...
What is the purpose of a stack? Why do we need it?
...ing coding, you should consider going for teaching programmers. Beside the fun, you could be making a killing without the pressures of business. Awesome flair is what you got in that area (and wonderful patience, I might add). I say that as an ex-university lecturer.
– Alan
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Extract elements of list at odd positions
...it be enumerate(L) instead of enumerate(items) ?
– ab123
May 24 '18 at 5:38
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Transitioning from Windows Forms to WPF
...lers that hide or resize, or what ever about UI,
It makes UI development fun. Especially once you find out how it likes to play along with Asyc processes. It really takes away a lot of the headaches that were caused by Winforms.
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Error handling in Bash
...ore on Github: github.com/Privex/shell-core
– Someguy123
Oct 8 '19 at 4:39
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Why isn't SQL ANSI-92 standard better adopted over ANSI-89?
...AS j USING(userid)
JOIN useraccounts AS us USING(userid)
WHERE j.jobid = 123
This is completely ambiguous. I put a UserID column in both Companies and user tables and there's no complaint. What if the UserID column in companies is the ID of the last person to modify that row?
I'm serious, Can ...
What is the purpose of wrapping whole Javascript files in anonymous functions like “(function(){ … }
...It's usually to namespace (see later) and control the visibility of member functions and/or variables. Think of it like an object definition. The technical name for it is an Immediately Invoked Function Expression (IIFE). jQuery plugins are usually written like this.
In Javascript, you can nest fun...
How is Docker different from a virtual machine?
...he guest OS to create the illusion that the guest OS has its own hardware. Fun fact: Before 1998 it was thought to be impossible to achieve this on the x86 architecture because there was no way to do this kind of interception. The folks at VMware were the first who had an idea to rewrite the executa...