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Assignment inside lambda expression in Python
I have a list of objects and I want to remove all objects that are empty except for one, using filter and a lambda expression.
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Printing without newline (print 'a',) prints a space, how to remove?
... This will consume a bit of memory for the string, but only make a single call to print. Note that string concatenation using += is now linear in the size of the string you're concatenating so this will be fast.
>>> for i in xrange(20):
... s += 'a'
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>>> print s
aaaaaaaaaa...
C++ display stack trace on exception
...re details.
On MSVC then you can use the StackWalker library that handles all of the underlying API calls needed for Windows.
You'll have to figure out the best way to integrate this functionality into your app, but the amount of code you need to write should be minimal.
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Regular expression to allow spaces between words
I want a regular expression that prevents symbols and only allows letters and numbers. The regex below works great, but it doesn't allow for spaces between words.
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Find current directory and file's directory [duplicate]
...tive to the current working directory and is not changed by an os.chdir() call.)
To get the current working directory use
import os
cwd = os.getcwd()
Documentation references for the modules, constants and functions used above:
The os and os.path modules.
The __file__ constant
os.path.rea...
Getting Java version at runtime
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Wow, that kind of blew my mind. Though in my case, all I wanted was the first two parts of the version so: Runtime.class.getPackage().getSpecificationVersion()
– Wesley Hartford
Dec 10 '14 at 21:44
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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:...
Are HLists nothing more than a convoluted way of writing tuples?
I am really interested in finding out where the differences are, and more generally, to identify canonical use cases where HLists cannot be used (or rather, don't yield any benefits over regular lists).
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JSON datetime between Python and JavaScript
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The lambda can be adapted to call the base implementation on non-datetime types, so TypeError can be raised if needed: dthandler = lambda obj: obj.isoformat() if isinstance(obj, datetime) else json.JSONEncoder().default(obj)
– Pascal...
How to disable HTML button using JavaScript?
I’ve read that you can disable (make physically unclickable) an HTML button simply by appending disable to its tag, but not as an attribute, as follows:
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