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Difference between 'new operator' and 'operator new'?
...ually try to phrase things differently to differentiate between the two a bit better, but it's a good question in any case.
Operator new is a function that allocates raw memory -- at least conceptually, it's not much different from malloc(). Though it's fairly unusual unless you're writing somethin...
INNER JOIN vs LEFT JOIN performance in SQL Server
...NNER JOIN to LEFT JOIN because the performance of LEFT JOIN is better, despite what I know. After I changed it, the speed of query got significantly improved.
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Why doesn't C# support the return of references?
...he great question!
The C# team is considering this for C# 7. See https://github.com/dotnet/roslyn/issues/5233 for details.
UPDATE: The feature made it in to C# 7!
You are correct; .NET does support methods that return managed references to variables. .NET also supports local variables that cont...
What's a concise way to check that environment variables are set in a Unix shell script?
..."}
: ${DEST:?"Need to set DEST non-empty"}
Or, better (see section on 'Position of double quotes' below):
: "${STATE?Need to set STATE}"
: "${DEST:?Need to set DEST non-empty}"
The first variant (using just ?) requires STATE to be set, but STATE="" (an empty string) is OK — not exactly what you ...
How can I safely create a nested directory?
... is the most elegant way to check if the directory a file is going to be written to exists, and if not, create the directory using Python? Here is what I tried:
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Understanding generators in Python
...cookbook at the moment and am currently looking at generators. I'm finding it hard to get my head round.
12 Answers
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Looking for a good world map generation algorithm [closed]
I'm working on a Civilization-like game and I'm looking for a good algorithm for generating Earth-like world maps. I've experimented with a few alternatives, but haven't hit on a real winner yet.
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ValidateRequest=“false” doesn't work in Asp.Net 4
I have a form at which I use ckeditor. This form worked fine at Asp.Net 2.0 and 3.5 but now it doesn't work in Asp.Net 4+. I have ValidateRequest="false" directive. Any suggestions?
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Test if a variable is a list or tuple
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Go ahead and use isinstance if you need it. It is somewhat evil, as it excludes custom sequences, iterators, and other things that you might actually need. However, sometimes you need to behave differently if someone, for instance, passes a string. My preference...
How to add an integer to each element in a list?
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This talk explains it: Facts and Myths about Python Names and Values: nedbatchelder.com/text/names1.html
– Ned Batchelder
Dec 2 '16 at 13:36
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