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regex for zip-code
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^\d{5}(?:[-\s]\d{4})?$
^ = Start of the string.
\d{5} = Match 5 digits (for condition 1, 2, 3)
(?:…) = Grouping
[-\s] = Match a space (for condition 3) or a hyphen (for condition 2)
\d{4} = Match 4 digits (for condition 2, 3)
…? = The pattern before it is optional...
Why is early return slower than else?
...()
[0.30939889008243426, 0.3035132258429485, 0.3046679117038593]
Considering that the bytecode is identical, the only difference is the name of the function. In particular the timing test does a lookup on the global name. Try renaming without_else() and the difference disappears:
>>> def...
How to open a file using the open with statement
I'm looking at how to do file input and output in Python. I've written the following code to read a list of names (one per line) from a file into another file while checking a name against the names in the file and appending text to the occurrences in the file. The code works. Could it be done bette...
What does @synchronized() do as a singleton method in objective C?
I just created a singleton method, and I would like to know what the function @synchronized() does, as I use it frequently, but do not know the meaning.
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What are the differences between Helper and Utility classes?
How determine how call a class XHelper or XUtils ?
5 Answers
5
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Is PHP's count() function O(1) or O(n) for arrays?
...t/standard/array.c
PHP_FUNCTION(count) calls php_count_recursive(), which in turn calls zend_hash_num_elements() for non-recursive array, which is implemented this way:
ZEND_API int zend_hash_num_elements(const HashTable *ht)
{
IS_CONSISTENT(ht);
return ht->nNumOfElements;
}
So you c...
How do I add a path to PYTHONPATH in virtualenv
I am trying to add a path to the PYTHONPATH environment variable, that would be only visible from a particular virtualenv environment.
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How to disable zoom on Ctrl+scroll in Visual Studio 2010?
Visual Studio 2010 adds a zoom setting on the bottom left of the text editor (to the left of the horizontal scroll bar) and also adopts the Ctrl +mouse scroll idiom for zooming in and out.
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SELECT INTO using Oracle
I'm trying to do a SELECT INTO using Oracle. My query is:
3 Answers
3
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Use logging print the output of pprint
I want to use pprint's output to show a complex data structure, but I would like to output it using the logging module rather than stdout.
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