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How to cast List to List
... No, it isn't. You would circumvent type safety if the above was allowed. Note that casting does not mean create a new list and copy over the items. It means handle the single instance as a different type, and thus you would have a list that contains potentially non-Customer objects with a...
Why was the switch statement designed to need a break?
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Many answers seem to focus on the ability to fall through as the reason for requiring the break statement.
I believe it was simply a mistake, due largely because when C was designed there was not nearly as much experience with how these constructs would be used.
Peter ...
Vagrant reverse port forwarding?
I'm working on a web services architecture. I've got some software that I need to run on the native host machine, not in Vagrant. But I'd like to run some client services on the guest.
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Android studio - Failed to find target android-18
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I think you might not have the Android-18 sdk installed. Go to Tools > Android > SDK Manager and check to see if Android 4.3 (API 18) is installed.
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How to know/change current directory in Python shell?
...now how to change.
edit
Under Windows:
set PYTHONPATH=%PYTHONPATH%;C:\My_python_lib
(taken from http://docs.python.org/using/windows.html)
edit 2
... and even better: use virtualenv and virtualenv_wrapper, this will allow you to create a development environment where you can add module paths ...
Xcode stuck at “Your application is being uploaded”
... just keep your head cool and check this first method:
Check if your firewall protection is off. If not then turn it off. It maybe blocking you to connect your computer with iTunes
Store.
Try a different internet connection. The purpose for trying a different internet connection is that your curre...
Best way to find the intersection of multiple sets?
... want here, but in case you ever need a generalisation of "take the sum of all these", "take the product of all these", "take the xor of all these", what you are looking for is the reduce function:
from operator import and_
from functools import reduce
print(reduce(and_, [{1,2,3},{2,3,4},{3,4,5}]))...
Random row selection in Pandas dataframe
... Thanks @eumiro. I also worked out that df.ix[np.random.random_integers(0, len(df), 10)] would also work.
– John
Apr 10 '13 at 10:58
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Can we have multiple in same ?
...tag should follow the opening table tag. developer.mozilla.org/en-US/docs/Web/HTML/Element/table
– Cypher
Jan 16 '14 at 7:53
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How do I execute a command and get the output of the command within C++ using POSIX?
...use the C stdio API, I prefer the iostreams API. popen requires you to manually clean up the FILE handle, pstreams do that automatically. popen only accepts a const char* for the argument, which requires care to avoid shell injection attacks, pstreams allows you to pass a vector of strings similar t...