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Why would you use an ivar?

...d by the compiler may involve another C function call to the functions objc_getProperty/objc_setProperty, as these will have to retain/copy/autorelease the objects as needed and further perform spinlocking for atomic properties where necessary. This can easily get very expensive and I'm not talking ...
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Where should signal handlers live in a django project?

...ke: yourapp/signals/handlers.py: from django.db.models.signals import pre_save from django.dispatch import receiver from myapp.models import MyModel @receiver(pre_save, sender=MyModel) def my_handler(sender, **kwargs): pass The best place to register your signal handler is then in the AppCo...
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namedtuple and default values for optional keyword arguments

...Node() Node(val=None, left=None, right=None) Before Python 3.7 Set Node.__new__.__defaults__ to the default values. >>> from collections import namedtuple >>> Node = namedtuple('Node', 'val left right') >>> Node.__new__.__defaults__ = (None,) * len(Node._fields) >&g...
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How to duplicate sys.stdout to a log file?

...ileno()) print "\nstdout" print >>sys.stderr, "stderr" os.spawnve("P_WAIT", "/bin/ls", ["/bin/ls"], {}) os.execve("/bin/ls", ["/bin/ls"], os.environ) You could also emulate tee using the multiprocessing package (or use processing if you're using Python 2.5 or earlier). Update Here is a Py...
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How to measure time in milliseconds using ANSI C?

...on many systems. You can use this function like this: struct timeval tval_before, tval_after, tval_result; gettimeofday(&tval_before, NULL); // Some code you want to time, for example: sleep(1); gettimeofday(&tval_after, NULL); timersub(&tval_after, &tval_before, &tval_resu...
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Python mysqldb: Library not loaded: libmysqlclient.18.dylib

... a slightly different spot: sudo ln -s /usr/local/mysql-5.5.29-osx10.6-x86_64/lib/libmysqlclient.18.dylib /usr/lib/libmysqlclient.18.dylib – Matt Apr 2 '14 at 16:35 ...
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How to pattern match using regular expression in Scala?

...ter match { case Pattern(c) => c bound to capture group here case _ => } share | improve this answer | follow | ...
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Python hashable dicts

...another dictionary for obvious reasons. class hashabledict(dict): def __hash__(self): return hash(tuple(sorted(self.items()))) share | improve this answer | fol...
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Understanding Python super() with __init__() methods [duplicate]

...ady. Note that the syntax changed in Python 3.0: you can just say super().__init__() instead of super(ChildB, self).__init__() which IMO is quite a bit nicer. The standard docs also refer to a guide to using super() which is quite explanatory. ...
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How does functools partial do what it does?

...g like this (apart from keyword args support etc): def partial(func, *part_args): def wrapper(*extra_args): args = list(part_args) args.extend(extra_args) return func(*args) return wrapper So, by calling partial(sum2, 4) you create a new function (a callable, to b...