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How to avoid “if” chains?
...ep<X>() should evaluate only if the previous one succeeded (this is called short circuit evaluation)
executeThisFunctionInAnyCase() will be executed in any case
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Django migration strategy for renaming a model and relationship fields
...n files (!).
Update: As ceasaro mentions, newer versions of Django are usually able to detect and ask if a model is renamed. So try manage.py makemigrations first and then check the migration file.
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The difference between fork(), vfork(), exec() and clone()
...d I expected there to be a huge amount of information on this, but there really wasn't any solid comparison between the four calls.
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Getter and Setter?
...
That's not really setter and getter. Typically I need for each property different implementation of getter!
– sumid
Feb 16 '13 at 0:59
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How to make a class JSON serializable
...t;>> magic(f)
'{"fname": "/foo/bar"}'
In that case you can merely call json.dumps(f.__dict__).
If you want more customized output then you will have to subclass JSONEncoder and implement your own custom serialization.
For a trivial example, see below.
>>> from json import JSONE...
Convert nested Python dict to object?
...; s.a
1
>>> s.b
{'c': 2}
>>> s.c
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'MyStruct' object has no attribute 'c'
>>> s.d
['hi']
The alternative (original answer contents) is:
class Struct:
def __init__(self...
Get name of object or class
...(function(){}); new myclass prints myclass {}
– Hugh Allen
May 26 '14 at 4:09
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What are good uses for Python3's “Function Annotations”
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I think this is actually great.
Coming from an academic background, I can tell you that annotations have proved themselves invaluable for enabling smart static analyzers for languages like Java. For instance, you could define semantics like sta...
Ruby send vs __send__
...ss being manipulated defines. It could have overriden send.
Watch:
class Foo
def bar?
true
end
def send(*args)
false
end
end
foo = Foo.new
foo.send(:bar?)
# => false
foo.__send__(:bar?)
# => true
If you override __send__, Ruby will emit a warning:
warning: redefining ...
How do I use a custom deleter with a std::unique_ptr member?
...is solution is that it doubles the overhead of every unique_ptr (they must all store the function pointer along with the pointer to the actual data), requires passing the destruction function every time, it can't inline (since the template can't specialize to the specific function, only the signatur...