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Why is “if not someobj:” better than “if someobj == None:” in Python?
...An empty string is false."
False, 0, (), [], {} and "" are all different from None, so your two code snippets are not equivalent.
Moreover, consider the following:
>>> False == 0
True
>>> False == ()
False
if object: is not an equality check. 0, (), [], None, {}, etc. are all...
Finding duplicates in O(n) time and O(1) space
Input: Given an array of n elements which contains elements from 0 to n-1, with any of these numbers appearing any number of times.
...
Docker build “Could not resolve 'archive.ubuntu.com'” apt-get fails to install anything
...
}
Exit from root:
# exit
Now restart docker:
$ sudo service docker restart
VERIFICATION:
Now check that adding the /etc/docker/daemon.json file allows you to resolve 'google.com' into an IP address:
$ docker run --rm busybox...
How to check that an element is in a std::set?
...his works with more containers but requires std::begin and std::end
// from C++0x, which you can get either:
// 1. By using a C++0x compiler or
// 2. Including the utility functions below.
return contains(std::begin(container), std::end(container), value);
// This works pre-C+...
MySQL: multiple tables or one table with many columns?
...e a relatively small length limit (~8000 bytes). In my problem table (data from very lengthy insurance forms, more than 100 columns) we have multiple varchar columns, all UTF8. So we easily filled the ~8000 bytes limit and got "error 139 from storage engine" all the time. So we had to split the tabl...
How do I parse a string to a float or int?
...ueError: invalid literal for int() with base 10: '545.222', but converting from a float to an int is a supported conversion.
– David Parks
May 7 '18 at 17:46
4
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ASP.NET MVC JsonResult Date Format
...299886.aspx#intro_to_json_topic2 for a better explanation (scroll down to "From JavaScript Literals to JSON")
One of the sore points of JSON is the
lack of a date/time literal. Many
people are surprised and disappointed
to learn this when they first
encounter JSON. The simple explanation...
What is SOA “in plain english”? [closed]
...rvice a cafe, or just take the soup and combine it with a bread you bought from another company to provide a cheaper menu, or let other restaurants use your salads to combine with their dishes, etc.
One of the most successful implementation of SOA was at Amazon. Because of their design, they could ...
Difference between Document-based and Key/Value-based databases?
...-value stores like redit doesn't allow you to store nested key:values? And from your description, then storing a whole database (from RDBMS) into Cassandra doesn't sound very clever cause it doesn't allow flexible query and has limited nesting depth, am I right?
– never_had_a_n...
Full screen in WPF application
...le dimensions.
I'd like my application to run in full screen independently from its dimensions.
2 Answers
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