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When to use in vs ref vs out
Someone asked me the other day when they should use the parameter keyword out instead of ref . While I (I think) understand the difference between the ref and out keywords (that has been asked before ) and the best explanation seems to be that ref == in and out , what are some (hypothet...
Why doesn't Python have a sign function?
...dge cases - which sometimes might require the call to cmp(x,0).
I don't know why it's not a built-in, but I have some thoughts.
copysign(x,y):
Return x with the sign of y.
Most importantly, copysign is a superset of sign! Calling copysign with x=1 is the same as a sign function. So you could...
Can I call a constructor from another constructor (do constructor chaining) in C++?
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JohnIdolJohnIdol
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Groovy: what's the purpose of “def” in “def x = 0”?
In the following piece of code (taken from the Groovy Semantics Manual page ), why prefix the assignment with the keyword def ?
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Starting python debugger automatically on error
... across, let's say an IndexError, python prints the line, location and quick description of the error and exits. Is it possible to automatically start pdb when an error is encountered? I am not against having an extra import statement at the top of the file, nor a few extra lines of code.
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How do I upgrade PHP in Mac OS X?
I feel this is an awfully obtuse question to ask, but strangely, this problem is poorly documented.
13 Answers
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C# DateTime to UTC Time without changing the time
...ateTime dt = DateTime.Now;
Console.WriteLine("{0} {1}", dt, dt.Kind);
DateTime ut = DateTime.SpecifyKind(dt, DateTimeKind.Utc);
Console.WriteLine("{0} {1}", ut, ut.Kind);
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How I can I lazily read multiple JSON values from a file/stream in Python?
I'd like to read multiple JSON objects from a file/stream in Python, one at a time. Unfortunately json.load() just .read() s until end-of-file; there doesn't seem to be any way to use it to read a single object or to lazily iterate over the objects.
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sql primary key and index
Say I have an ID row (int) in a database set as the primary key. If I query off the ID often do I also need to index it? Or does it being a primary key mean it's already indexed?
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Can I set up HTML/Email Templates with ASP.NET?
I'm working on a site that will send out a significant number of emails. I want to set up both header and footer text, or maybe even templates to allow the users to easily edit these emails if they need to.
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