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Serializing class instance to JSON
I am trying to create a JSON string representation of a class instance and having difficulty. Let's say the class is built like this:
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unique object identifier in javascript
I need to do some experiment and I need to know some kind of unique identifier for objects in javascript, so I can see if they are the same. I don't want to use equality operators, I need something like the id() function in python.
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What is the purpose of the -m switch?
...line of the Rationale section of PEP 338 says:
Python 2.4 adds the command line switch -m to allow modules to be located using the Python module namespace for execution as scripts. The motivating examples were standard library modules such as pdb and profile, and the Python 2.4 implementation is...
Object of custom type as dictionary key
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You need to add 2 methods, note __hash__ and __eq__:
class MyThing:
def __init__(self,name,location,length):
self.name = name
self.location = location
self.length = length
def __hash__(self):
return hash((self.name, self.lo...
Inherit docstrings in Python class inheritance
I'm trying to do some class inheritance in Python. I'd like each class and inherited class to have good docstrings. So I think for the inherited class, I'd like it to:
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How can I dynamically create derived classes from a base class
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This bit of code allows you to create new classes with dynamic
names and parameter names.
The parameter verification in __init__ just does not allow
unknown parameters, if you need other verifications, like
type, or that they are mandatory, just add the logic
there:
class BaseClass(object):...
What's the pythonic way to use getters and setters?
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What's the pythonic way to use getters and setters?
The "Pythonic" way is not to use "getters" and "setters", but to use plain attributes, like the question demonstrates, and del for deleting (but the names are changed to protect the innocent... builtins):
valu...
Python constructors and __init__
Why are constructors indeed called "Constructors"? What is their purpose and how are they different from methods in a class?
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Why is “if not someobj:” better than “if someobj == None:” in Python?
... the object has a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero.
Otherwise, if the object has a __len__ special method (as do contain...
Why does Python code use len() function instead of a length method?
...tocol in Python is to implement this method on objects which have a length and use the built-in len() function, which calls it for you, similar to the way you would implement __iter__() and use the built-in iter() function (or have the method called behind the scenes for you) on objects which are it...