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Should import statements always be at the top of a module?
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Module importing is quite fast, but not instant. This means that:
Putting the imports at the top of the module is fine, because it's a trivial cost that's only paid once.
Putting the imports within a function will cause calls to that function to take long...
What are forward declarations in C++?
... wants to ensure you haven't made spelling mistakes or passed the wrong number of arguments to the function. So, it insists that it first sees a declaration of 'add' (or any other types, classes or functions) before it is used.
This really just allows the compiler to do a better job of validating t...
Does “\d” in regex mean a digit?
I found that in 123 , \d matches 1 and 3 but not 2 . I was wondering if \d matches a digit satisfying what kind of requirement? I am talking about Python style regex.
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Mutable vs immutable objects
I'm trying to get my head around mutable vs immutable objects. Using mutable objects gets a lot of bad press (e.g. returning an array of strings from a method) but I'm having trouble understanding what the negative impacts are of this. What are the best practices around using mutable objects? Should...
What does the construct x = x || y mean?
I am debugging some JavaScript, and can't explain what this || does?
12 Answers
12
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Get operating system info
I recently started wondering about sites like http://thismachine.info/ that get the user's operating system info. I have not been able to find out how to do that with PHP, and wanted to try to figure it out.
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Difference between HEAD and master
What is the difference between the HEAD and master in Git?
3 Answers
3
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Technically, why are processes in Erlang more efficient than OS threads?
From Erlang Programming (2009):
7 Answers
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Adding days to a date in Python
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The previous answers are correct but it's generally a better practice to do:
import datetime
Then you'll have, using datetime.timedelta:
date_1 = datetime.datetime.strptime(start_date, "%m/%d/%y")
end_date = date_1 + datetime.timedelta(days=10)
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How do I break a string over multiple lines?
In YAML, I have a string that's very long. I want to keep this within the 80-column (or so) view of my editor, so I'd like to break the string. What's the syntax for this?
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