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Does Python support short-circuiting?
...circuiting "executed" not printed
1
>>> 1 and fun(1) # fun(1) called and "executed" printed
executed
1
>>> 0 and fun(1) # due to short-circuiting "executed" not printed
0
Note: The following values are considered by the interpreter to mean false:
False None ...
Fastest way to get the first object from a queryset in django?
...eturn None if there aren't any. There are lots of ways to do this which all work. But I'm wondering which is the most performant.
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What optimizations can GHC be expected to perform reliably?
...has a lot of optimizations that it can perform, but I don't know what they all are, nor how likely they are to be performed and under what circumstances.
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Correct owner/group/permissions for Apache 2 site files/folders under Mac OS X?
...go-rwx DIR (nobody other than owner can access content)
chmod go+x DIR (to allow "users" including _www to "enter" the dir)
sudo chgrp -R _www ~/my/web/root (all web content is now group _www)
chmod -R go-rwx ~/my/web/root (nobody other than owner can access web content)
chmod -R g+rx ~/my/web/root...
How can you encode a string to Base64 in JavaScript?
... in 8 bits, it will probably break. This isn’t a problem if you’re actually treating the string as a byte array, but if you’re trying to do something else then you’ll have to encode it first.
atob() returns a “string” where each character represents an 8-bit byte – that is, its value w...
List directory tree structure in python?
I know that we can use os.walk() to list all sub-directories or all files in a directory. However, I would like to list the full directory tree content:
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What is the most effective way for float and double comparison?
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Be extremely careful using any of the other suggestions. It all depends on context.
I have spent a long time tracing a bugs in a system that presumed a==b if |a-b|<epsilon. The underlying problems were:
The implicit presumption in an algorithm that if a==b and b==c then a==c.
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'printf' vs. 'cout' in C++
...letely on operator overloading, so there is no issue with custom formats - all you do is define a subroutine taking std::ostream as the first argument and your type as second. As such, there are no namespace problems - as long you have a class (which isn't limited to one character), you can have wor...
How to write a Python module/package?
I've been making Python scripts for simple tasks at work and never really bothered packaging them for others to use. Now I have been assigned to make a Python wrapper for a REST API. I have absolutely no idea on how to start and I need help.
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How can I get the client's IP address in ASP.NET MVC?
I'm totally new to the ASP.NET MVC stack, and I was wondering what happened to the simple Page object and the Request ServerVariables object?
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