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How to check whether dynamically attached event listener exists or not?

... finally? If you wanted to you could something like the following: var _addEventListener = EventTarget.prototype.addEventListener; var _removeEventListener = EventTarget.prototype.removeEventListener; EventTarget.prototype.events = {}; EventTarget.prototype.addEventListener = function(name, list...
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Delete multiple objects in django

... to delete any Post with a future publication date Post.objects.filter(pub_date__gt=datetime.now()).delete() You do, however, need to come up with a way to narrow down your QuerySet. If you just want a view to delete a particular object, look into the delete generic view. EDIT: Sorry for the mi...
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Initializing a list to a known number of elements in Python [duplicate]

...x in xrange(N)] 10 loops, best of 3: 109 ms per loop >>> def fill_list1(): """Not too bad, but complicated code""" a = [None] * N for x in xrange(N): a[x] = x**2 >>> %timeit fill_list1() 10 loops, best of 3: 126 ms per loop >>> def fill_list2(): "...
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str performance in python

...; import dis >>> dis.dis(lambda: str(100000)) 8 0 LOAD_GLOBAL 0 (str) 3 LOAD_CONST 1 (100000) 6 CALL_FUNCTION 1 9 RETURN_VALUE >>> dis.dis(lambda: '%s' % 100000) 9 0 LOAD...
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Declare and Initialize String Array in VBA

... Dim myStringArray() As String *code* redim myStringArray(size_of_your_array) Then you can do something static like this: myStringArray = { item_1, item_2, ... } Or something iterative like this: Dim x For x = 0 To size_of_your_array myStringArray(x) = data_source(x).Name Nex...
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Default template arguments for function templates

... typename Comp = std::less< typename std::iterator_traits<Iterator>::value_type> > void sort(Iterator beg, Iterator end, Comp c = Comp()) { ... } C++0x introduces them to C++. See this defect report by Bjarne Stroustrup: Default Template Arguments for Functio...
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What is a NullReferenceException, and how do I fix it?

...ic class Form1 { private Customer customer; private void Form1_Load(object sender, EventArgs e) { Customer customer = new Customer(); customer.Name = "John"; } private void Button_Click(object sender, EventArgs e) { MessageBox.Show(customer....
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How can I count the occurrences of a list item?

...by a constant factor of approximately 2. Here is the script I used: from __future__ import print_function import timeit t1=timeit.Timer('Counter(l)', \ 'import random;import string;from collections import Counter;n=1000;l=[random.choice(string.ascii_letters) for x in range(n)]' ...
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Can jQuery provide the tag name?

... $(this).attr("id", "rnd" + $(this).attr("tag") + "_" + i.toString()); should be $(this).attr("id", "rnd" + this.nodeName.toLowerCase() + "_" + i.toString()); share | imp...
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How to get all subsets of a set? (powerset)

...3,) (1,2) (1,3) (2,3) (1,2,3)" s = list(iterable) return chain.from_iterable(combinations(s, r) for r in range(len(s)+1)) Output: >>> list(powerset("abcd")) [(), ('a',), ('b',), ('c',), ('d',), ('a', 'b'), ('a', 'c'), ('a', 'd'), ('b', 'c'), ('b', 'd'), ('c', 'd'), ('a', 'b', 'c'...