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Python `if x is not None` or `if not x is None`?
...he if not x is None version to be more clear, but Google's style guide and PEP-8 both use if x is not None . Is there any minor performance difference (I'm assuming not), and is there any case where one really doesn't fit (making the other a clear winner for my convention)?*
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Does using “new” on a struct allocate it on the heap or stack?
...ut where value type variables are allocated. That's a different question - and one to which the answer isn't just "on the stack". It's more complicated than that (and made even more complicated by C# 2). I have an article on the topic and will expand on it if requested, but let's deal with just the ...
How to avoid explicit 'self' in Python?
...ying self. The result is there's never any confusion over what's a member and what's not, even without the full class definition visible. This leads to useful properties, such as: you can't add members which accidentally shadow non-members and thereby break code.
One extreme example: you can writ...
Can I mix Swift with C++? Like the Objective-C .mm files
I just changed my .m files to .mm and use C++. Is there a way to do the same with Swift?
13 Answers
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How to get URL parameter using jQuery or plain JavaScript?
I have seen lots of jQuery examples where parameter size and name are unknown.
33 Answers
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How to find first element of array matching a boolean condition in JavaScript?
...for arrays; this stops enumerating the array once it finds the first match and returns the value.
const result = someArray.find(isNotNullNorUndefined);
Old answer:
I have to post an answer to stop these filter suggestions :-)
since there are so many functional-style array methods in ECMAScript, p...
What do Clustered and Non clustered index actually mean?
I have a limited exposure to DB and have only used DB as an application programmer. I want to know about Clustered and Non clustered indexes .
I googled and what I found was :
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How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simp...
Why is there no String.Empty in Java?
I understand that every time I type the string literal "" , the same String object is referenced in the string pool.
11 An...
Can I use an OR in regex without capturing what's enclosed?
I'm using rubular.com to build my regex, and their documentation describes the following:
4 Answers
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