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Is it possible to declare a variable in Python, like so?:
var so that it initialized to None? It seems like Python allows this, but as soon as you access it, it crashes. Is this possible? If not, why?
EDIT: I want to do this for cases like this:
value for index in sequence: if value == None and conditionMet: value = index break 
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To declare a variable without a value in Python, use the value “None”. You can also use what Python calls “type hints” to declare a variable without a value. When working with variables in Python, sometimes it makes sense to initialize a variable, but not assign it any value.
Still, this is a common question asked by many programmers that can we declare any variable without any value? The answer is: "Yes! We can declare such type of variable". To declare a variable without any variable, just assign None.
Python is dynamic, so you don't need to declare things; they exist automatically in the first scope where they're assigned. So, all you need is a regular old assignment statement that assigns None to the variable.
In order to define a null variable, you can use the None keyword. Note: The None keyword refers to a variable or object that is empty or has no value. It is Python's way of defining null values.
Why not just do this:
var = None Python is dynamic, so you don't need to declare things; they exist automatically in the first scope where they're assigned. So, all you need is a regular old assignment statement as above.
This is nice, because you'll never end up with an uninitialized variable. But be careful -- this doesn't mean that you won't end up with incorrectly initialized variables. If you init something to None, make sure that's what you really want, and assign something more meaningful if you can.
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