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Abstract methods in Python [duplicate]
I am having trouble in using inheritance with Python. While the concept seems too easy for me in Java yet up till now I have been unable to understand in Python which is surprising to me at least.
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What exactly are unmanaged resources?
...nmanaged resources correctly, the garbage collector will eventually handle it for you when the object containing that resource is garbage collected (this is "finalization"). But because the garbage collector doesn't know about the unmanaged resources, it can't tell how badly it needs to release them...
What it the significance of the Javascript constructor property?
...r, the significance of the constructor property, as I can't seem to make it have any effect. E.g.:
6 Answers
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Why is exception handling bad?
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Exceptions make it really easy to write code where an exception being thrown will break invariants and leave objects in an inconsistent state. They essentially force you to remember that most every statement you make can potentially throw, ...
mysqli or PDO - what are the pros and cons? [closed]
In our place we're split between using mysqli and PDO for stuff like prepared statements and transaction support. Some projects use one, some the other. There is little realistic likelihood of us ever moving to another RDBMS.
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How to access the correct `this` inside a callback?
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this (aka "the context") is a special keyword inside each function and its value only depends on how the function was called, not how/when/where it was defined. It is not affected by lexical scopes like other variables (except for arrow functions, see below). Here are some examples:
function foo...
When and why will a compiler initialise memory to 0xCD, 0xDD, etc. on malloc/free/new/delete?
I know that the compiler will sometimes initialize memory with certain patterns such as 0xCD and 0xDD . What I want to know is when and why this happens.
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What does Maven do, in theory and in practice? When is it worth to use it? [closed]
... for practice. I've read about Maven, but I don't actually understand when it is meant to be used.
3 Answers
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How do I return the response from an asynchronous call?
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→ For a more general explanation of async behaviour with different examples, please see Why is my variable unaltered after I modify it inside of a function? - Asynchronous code reference
→ If you already understand the problem, skip to the possible solutions below.
The probl...
Why does the is operator return false when given null?
It seems to me that the is operator is a bit inconsistent.
7 Answers
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