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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...
Capturing URL parameters in request.GET
...ll find the request method (in this case "GET", and for submitted forms usually "POST") in request.method. In some cases it's useful to check that it matches what you're expecting.
Update: When deciding whether to use the URL path or the query parameters for passing information, the following may h...
How much faster is Redis than mongoDB?
...benchmarks that test your case and link from this post instead, then we'll all benefit from your "tested" opinion.
– Homer6
Jan 7 '13 at 18:38
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Python argparse mutual exclusive group
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add_mutually_exclusive_group doesn't make an entire group mutually exclusive. It makes options within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd have:
p...
Perl flags -pe, -pi, -p, -w, -d, -i, -t?
...eem to be mostly made up of punctuation :-)
The command line switches are all detailed in perlrun. (available from the command line by calling perldoc perlrun)
Going into the options briefly, one-by-one:
-p: Places a printing loop around your command so that it acts on each
line of standard ...
How do you express binary literals in Python?
... memory.
Note that leading zeros in a non-zero decimal number are not allowed.
This is for disambiguation with C-style octal literals, which Python
used before version 3.0.
Some examples of integer literals:
7 2147483647 0o177 0b100110111
3 7922816251...
Why can I access TypeScript private members when I shouldn't be able to?
...bers in TypeScript, and I find it a little confusing. Intellisense doesn't allow to access private member, but in pure JavaScript, it's all there. This makes me think that TS doesn't implement private members correctly.
Any thoughts?
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Print multiple arguments in Python
...or", name, "is", score)
If you don't want spaces to be inserted automatically by print in the above example, change the sep parameter:
print("Total score for ", name, " is ", score, sep='')
If you're using Python 2, won't be able to use the last two because print isn't a function in Python 2. Y...
Loop backwards using indices in Python?
... This is better than the accepted answer since it doesn't actually allocate all the numbers in memory (in Python 3 the accepted answer wouldn't either), plus it's more obvious what is happening.
– Blixt
Mar 23 '12 at 13:52
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UIRefreshControl without UITableViewController
...ng a UIRefreshControl instance as a subview to my UITableView. And it magically just works!
UIRefreshControl *refreshControl = [[UIRefreshControl alloc] init];
[refreshControl addTarget:self action:@selector(handleRefresh:) forControlEvents:UIControlEventValueChanged];
[self.myTableView addSubview:...