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Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?
...o this already):
Cleanly exiting a function
Often in a function, you may allocate resources and need to exit in multiple places. Programmers can simplify their code by putting the resource cleanup code at the end of the function, and all "exit points" of the function would goto the cleanup label....
Is there a replacement for unistd.h for Windows (Visual C)?
...nsole program written for Unix to the Windows platform ( Visual C++ 8.0 ). All the source files include "unistd.h", which doesn't exist. Removing it, I get complaints about misssing prototypes for 'srandom', 'random', and 'getopt'.
I know I can replace the random functions, and I'm pretty sure I ca...
How to get the parents of a Python class?
...
If you want all the ancestors rather than just the immediate ones, use inspect.getmro:
import inspect
print inspect.getmro(cls)
Usefully, this gives you all ancestor classes in the "method resolution order" -- i.e. the order in which ...
Build a Basic Python Iterator
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Iterator objects in python conform to the iterator protocol, which basically means they provide two methods: __iter__() and __next__().
The __iter__ returns the iterator object and is implicitly called
at the start of loops.
The __next__() method returns the next value and is implicitly cal...
Understanding the difference between __getattr__ and __getattribute__
...oesn't explicitly manage and do that via __getattr__ method.
Python will call this method whenever you request an attribute that hasn't already been defined, so you can define what to do with it.
A classic use case:
class A(dict):
def __getattr__(self, name):
return self[name]
a = A()...
Absolute vs relative URLs
...ed Jan 5 '10 at 9:33
Daniel VassalloDaniel Vassallo
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Difference between exit(0) and exit(1) in Python
... code means a successful exit.
This is useful for other programs, shell, caller etc. to know what happened with your program and proceed accordingly.
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method of iterating over sqlalchemy model's defined columns?
...l exclude SA magic attributes, but will not exclude the relations. So basically it might load the dependencies, parents, children etc, which is definitely not desirable.
But it is actually much easier because if you inherit from Base, you have a __table__ attribute, so that you can do:
for c in Jo...
What is the most efficient way to store tags in a database?
...
Actually I believe de-normalising the tags table might be a better way forward, depending on scale.
This way, the tags table simply has tagid, itemid, tagname.
You'll get duplicate tagnames, but it makes adding/removing/editing...
What is the Difference Between Mercurial and Git?
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I work on Mercurial, but fundamentally I believe both systems are equivalent. They both work with the same abstractions: a series of snapshots (changesets) which make up the history. Each changeset knows where it came from (the parent changeset) and can have ...