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Days between two dates? [duplicate]
...u’ve literally got two date objects, you can subtract one from the other and query the resulting timedelta object for the number of days:
>>> from datetime import date
>>> a = date(2011,11,24)
>>> b = date(2011,11,17)
>>> a-b
datetime.timedelta(7)
>>> ...
How do I include negative decimal numbers in this regular expression?
...\d*(\.\d+)?$
I verified it in Rubular with these values:
10.00
-10.00
and both matched as expected.
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Convert NaN to 0 in javascript
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Thanks mate, have selected and modified a bit this for myself a = a*1 || 0
– Somebody
Dec 7 '11 at 17:22
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Getting the first character of a string with $str[0]
I want to get the first letter of a string and I've noticed that $str[0] works great. I am just not sure whether this is 'good practice', as that notation is generally used with arrays. This feature doesn't seem to be very well documented so I'm turning to you guys to tell me if it's all right –...
What's the difference between “mod” and “remainder”?
My friend said that there are differences between "mod" and "remainder".
5 Answers
5
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Where can I get a list of Ansible pre-defined variables?
...at Ansible provide some pre-defined variables that we can use in playbooks and template files. For example, the host ip address is ansible_eth0.ipv4.address. Googleing and searching the docs I cound't find a list of all available variables. Would someone list them for me?
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I do not want to inherit the child opacity from the parent in CSS
...d-color: rgba(0,0,255,0.5); this code is right, but does not work with ie6 and ie7
– Lion King
Apr 24 '11 at 12:10
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Why can't I center with margin: 0 auto?
I have a #header div that is 100% width and within that div I have an unordered list. I have applied margin: 0 auto to the unordered list but it won't center it within the header div.
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How is “=default” different from “{}” for default constructor and destructor?
...om simply doing {}. With the latter, the function becomes "user-provided". And that changes everything.
This is a trivial class by C++11's definition:
struct Trivial
{
int foo;
};
If you attempt to default construct one, the compiler will generate a default constructor automatically. Same goes...
In javascript, is an empty string always false as a boolean?
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Yes. Javascript is a dialect of ECMAScript, and ECMAScript language specification clearly defines this behavior:
ToBoolean
The result is false if the argument is the empty String (its length is zero);
otherwise the result is true
Quote taken from http://www.ecma-inte...