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Referring to the null object in Python
...
SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
Pass a parameter to a fixture function
... through the tester fixture.
I had a similar problem--I have a fixture called test_package, and I later wanted to be able to pass an optional argument to that fixture when running it in specific tests. For example:
@pytest.fixture()
def test_package(request, version='1.0'):
...
request....
Input and output numpy arrays to h5py
I have a Python code whose output is a sized matrix, whose entries are all of the type float . If I save it with the extension .dat the file size is of the order of 500 MB. I read that using h5py reduces the file size considerably. So, let's say I have the 2D numpy array named A . How do I ...
What is the best extension for SQLite database files? [closed]
...king about in the database by themselves. The program reads and writes it all by itself. The only reason for a user to touch the DB file is to take a backup copy. Therefore I have named it whatever_records.db
The simple .db extension tells the user that it is a binary data file and that's all the...
What's the best practice for primary keys in tables?
...
I follow a few rules:
Primary keys should be as small as necessary. Prefer a numeric type because numeric types are stored in a much more compact format than character formats. This is because most primary keys will be foreign keys in another table as well as used in multipl...
Creating a config file in PHP
...ne simple but elegant way is to create a config.php file (or whatever you call it) that just returns an array:
<?php
return array(
'host' => 'localhost',
'username' => 'root',
);
And then:
$configs = include('config.php');
...
Is the list of Python reserved words and builtins available in a library?
...break', 'class', 'continue', 'def',
'del', 'elif', 'else', 'except', 'finally', 'for', 'from', 'global', 'if', 'import',
'in', 'is', 'lambda', 'nonlocal', 'not', 'or', 'pass', 'raise', 'return', 'try',
'while', 'with', 'yield']
If you want to include built-in names as well (Python 3), then c...
Hibernate Annotations - Which is better, field or property access?
...d to add logic for", or "xxxx breaks encapsulation". However, nobody has really commented on the theory, and given a properly reasoned argument.
What is Hibernate/JPA actually doing when it persists an object - well, it is persisting the STATE of the object. That means storing it in a way that it ...
How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
... (you can see them in the first diagram), one for B and one for C who virtually inherit A. D's object size is increased because it stores 2 pointers now; however there is only one A now.
So B::A and C::A are the same and so there can be no ambiguous calls from D. If you don't use virtual inheri...
How do I get my Maven Integration tests to run
...he *Test not the *Integration.java files will run when executing: mvn install I need to run my *Test.java as the default, but for my nightlty build I need to run both *Test.java and *Integration.java. I have to execute mvn install then cd to each sub-child directory and execute mvn -Dtest=**/*In...