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Python: most idiomatic way to convert None to empty string?
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If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
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How to change a django QueryDict to Python Dict?
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In Django 1.8 on Python 3 all I needed was dict(queryDict).
– fmalina
May 15 '15 at 19:16
1
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Error to run Android Studio
I have installed Android Studio and I followed all steps described here
17 Answers
17...
Dynamically adding a form to a Django formset with Ajax
I want to automatically add new forms to a Django formset using Ajax, so that when the user clicks an "add" button it runs JavaScript that adds a new form (which is part of the formset) to the page.
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C++11 reverse range-based for-loop
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Actually Boost does have such adaptor: boost::adaptors::reverse.
#include <list>
#include <iostream>
#include <boost/range/adaptor/reversed.hpp>
int main()
{
std::list<int> x { 2, 3, 5, 7, 11, 13, 1...
In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...ld instances (at least,
not at the moment). If a base class has a field called author, you
cannot create another model field called author in any class that
inherits from that base class.
share
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Simple insecure two-way data “obfuscation”?
...e to figure out your keys by just assuming that you used this code as-is! All you have to do is change some of the numbers (must be <= 255) in the Key and Vector arrays (I left one invalid value in the Vector array to make sure you do this...). You can use https://www.random.org/bytes/ to gener...
What is a proper naming convention for MySQL FKs?
...constraints. If a name is not given, InnoDB creates a unique name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE T...
TypeScript static classes
...hat cannot be subclassed and must contain only static methods. C# does not allow one to define functions outside of classes. In TypeScript this is possible, however.
If you're looking for a way to put your functions/methods in a namespace (i.e. not global), you could consider using TypeScript's mod...
What is the “__v” field in Mongoose
... now, but I wanted something that I could put in the Schema directly so in all queries.
– diosney
Mar 24 '14 at 11:52
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