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List changes unexpectedly after assignment. How do I clone or copy it to prevent this?
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With new_list = my_list, you don't actually have two lists. The assignment just copies the reference to the list, not the actual list, so both new_list and my_list refer to the same list after the assignment.
To actually copy the list, you have various possibilit...
Programmatically retrieve memory usage on iPhone
...trieve the amount of memory my iPhone app is using at anytime, programmatically. Yes I'm aware about ObjectAlloc/Leaks. I'm not interested in those, only to know if it's possible to write some code and get the amount of bytes being used and report it via NSLog.
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jQuery Validate Plugin - Trigger validation of single field
I've got a form that can optionally be pre-populated via facebook connect. Once a user connects, their name and email are automatically filled in. The problem is that this doesn't trigger the remote validation to check if the email already exists.
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What is the best way to ensure only one instance of a Bash script is running? [duplicate]
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If the script is the same across all users, you can use a lockfile approach. If you acquire the lock, proceed else show a message and exit.
As an example:
[Terminal #1] $ lockfile -r 0 /tmp/the.lock
[Terminal #1] $
[Terminal #2] $ lockfile -r 0 /tmp/the....
How to get Linux console window width in Python
Is there a way in python to programmatically determine the width of the console? I mean the number of characters that fits in one line without wrapping, not the pixel width of the window.
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How to print third column to last column?
... Note that this only works if the delimiter is exactly the same between all columns... For example, you can't use cut with a delimiter like \d+. (That I know of.)
– Zach Wily
Jan 13 '10 at 21:11
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What is the reason why “synchronized” is not allowed in Java 8 interface methods?
...t seem sensible to extend this semantics to default methods as well; after all, they are instance methods with a receiver too. (Note that synchronized methods are entirely a syntactic optimization; they're not needed, they're just more compact than the corresponding synchronized block. There's a r...
Iterate a list as pair (current, next) in Python
...(b, None)
return itertools.izip(a, b)
How this works:
First, two parallel iterators, a and b are created (the tee() call), both pointing to the first element of the original iterable. The second iterator, b is moved 1 step forward (the next(b, None)) call). At this point a points to s0 and b...
Django: Get model from string?
...d in 1.9) in favor of the the new application loading system.
-- Scott Woodall
Found it. It's defined here:
from django.db.models.loading import get_model
Defined as:
def get_model(self, app_label, model_name, seed_cache=True):
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Specifying rails version to use when creating a new application
I have two versions of rails (2.1.0 and 2.2.2) installed in my computer.
7 Answers
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