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Is there an expression for an infinite generator?

... for x in iter(int, 1): pass Two-argument iter = zero-argument callable + sentinel value int() always returns 0 Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One va...
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How to find the width of a div using vanilla JavaScript?

... All Answers are right, but i still want to give some other alternatives that may work. If you are looking for the assigned width (ignoring padding, margin and so on) you could use. getComputedStyle(element).width; //returns...
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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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PHP mkdir: Permission denied problem

...te permissions on the directory. Here's what you do in Ubuntu Make sure all files are owned by the Apache group and user. In Ubuntu it is the www-data group and user chown -R www-data:www-data /path/to/webserver/www Next enabled all members of the www-data group to read and write files chmod -R...
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Multiprocessing vs Threading Python [duplicate]

... There is actually a good deal of difference: eli.thegreenplace.net/2012/01/16/… – Andrew Sledge May 29 '13 at 11:36 ...
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How to know if an object has an attribute in Python

...n is that, if the property is likely to be there most of the time, simply call it and either let the exception propagate, or trap it with a try/except block. This will likely be faster than hasattr. If the property is likely to not be there most of the time, or you're not sure, using hasattr will pr...
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Get ID of last inserted document in a mongoDB w/ Java driver

...h MongoDB plainly auto-generates ObjectId's. However, your solution of manually creating an ObjectId does work, and thanks for this option! – Apophenia Overload Dec 4 '12 at 8:39 ...
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Why doesn't django's model.save() call full_clean()?

...t curious if anyone knows if there's good reason why django's orm doesn't call 'full_clean' on a model unless it is being saved as part of a model form. ...
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ViewPager and fragments — what's the right way to store fragment's state?

...agment will be placed. FragmentPagerAdapter.getItem(int position) is only called when a fragment for that position does not exist. After rotating, Android will notice that it already created/saved a fragment for this particular position and so it simply tries to reconnect with it with FragmentManage...
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How to delete all Annotations on a MKMapView

Is there a simple way to delete all the annotations on a map without iterating through all the displayed annotations in Objective-c? ...