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Understanding garbage collection in .NET
... tinker with the source code. Note how the extra braces have no effect at all. And note how setting the variable to null makes no difference at all. It will always print "1". It now works the way you hope and expected it would work.
Which does leave with the task of explaining why it works so d...
How can I do a line break (line continuation) in Python?
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Actually, you have the style guide's preference exactly backwards. Implicit continuation is preferred, explicit backslash is to be used only if necessary.
– Carl Meyer
Sep 11 '08 at 19:00
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How to validate an email address using a regular expression?
...he IP address pattern that is floating around the internet with a bug that allows 00 for any of the unsigned byte decimal values in a dot-delimited address, which is illegal. The rest of it appears to be consistent with the RFC 5322 grammar and passes several tests using grep -Po, including cases d...
python max function using 'key' and lambda expression
... def. Thus, you can't use statements inside a lambda, only expressions are allowed.
What does max do?
max(a, b, c, ...[, key=func]) -> value
With a single iterable argument, return its largest item. With two or
more arguments, return the largest argument.
So, it simply returns the...
Why is reading lines from stdin much slower in C++ than Python?
...tl;dr: Because of different default settings in C++ requiring more system calls.
By default, cin is synchronized with stdio, which causes it to avoid any input buffering. If you add this to the top of your main, you should see much better performance:
std::ios_base::sync_with_stdio(false);
Normall...
python-pandas and databases like mysql
...rame from it. SQLAlchemy makes it easier to combine SQL conditions Pythonically if you intend to mix and match things over and over.
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Table
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from...
Why extend the Android Application class?
... are many uses of extending application class. One very useful is to catch all uncaught exceptions in you application. SO this is something which can be very handy
– png
Jun 18 '14 at 9:56
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How to split a file into equal parts, without breaking individual lines? [duplicate]
...s wondering if it was possible to split a file into equal parts ( edit: = all equal except for the last), without breaking the line? Using the split command in Unix, lines may be broken in half. Is there a way to, say, split up a file in 5 equal parts, but have it still only consist of whole lines ...
How to stop/terminate a python script from running?
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You can also do it if you use the exit() function in your code. More ideally, you can do sys.exit(). sys.exit() which might terminate Python even if you are running things in parallel through the multiprocessing package.
Note: In order to use the sys.exit(), you must import it: import sys
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How to export and import environment variables in windows?
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NOTE: This doesn't get all Environment Variables(EV)! I just did a command set path and messed up all my EV. I went to this registry and only the original EV were there. I did a system restore and got all my missing EV back to the PATH var. This re...