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Difference between exit() and sys.exit() in Python
...ython, there are two similarly-named functions, exit() and sys.exit() . What's the difference and when should I use one over the other?
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jQuery - prevent default, then continue default
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Yes that is exactly what the submit() function does.
– Ron van der Heijden
Jan 17 '13 at 9:02
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Can anyone explain IEnumerable and IEnumerator to me? [closed]
...at.Current
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}
By "functionally equivalent," I mean that's actually what the compiler turns the code into. You can't use foreach on baz in this example unless baz implements IEnumerable.
IEnumerable means that baz implements the method
IEnumerator GetEnumerator()
The IEnumerator object...
Python debugging tips [closed]
What are your best tips for debugging Python?
18 Answers
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How do you do relative time in Rails?
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What about
30.seconds.ago
2.days.ago
Or something else you were shooting for?
share
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Want to find records with no associated records in Rails
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Just imagine you have 10000000 records in friends table. What about performance in that case?
– goodniceweb
Dec 20 '16 at 14:51
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Benefits of inline functions in C++?
What is the advantages/disadvantages of using inline functions in C++? I see that it only increases performance for the code that the compiler outputs, but with today's optimized compilers, fast CPUs, huge memory etc. (not like in the 1980< where memory was scarce and everything had to fit in 100KB ...
JSON and XML comparison [closed]
...and there are plenty of good parsers which will change the details to make what I'm saying not quite valid.
JSON is both more compact and (in my view) more readable - in transmission it can be "faster" simply because less data is transferred.
In parsing, it depends on your parser. A parser turning...
Warning: Null value is eliminated by an aggregate or other SET operation in Aqua Data Studio
..., 0) is always non-null value, COUNT(ISNULL(field, 0)) counts rows. That's what COUNT(*) is for and not what the OP here was after.
– user743382
Mar 9 '16 at 15:56
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What is the most efficient/elegant way to parse a flat table into a tree?
... are several ways to store tree-structured data in a relational database. What you show in your example uses two methods:
Adjacency List (the "parent" column) and
Path Enumeration (the dotted-numbers in your name column).
Another solution is called Nested Sets, and it can be stored in the ...