Python string interning
While this question doesn’t have any real use in practice, I am curious as to how Python does string interning. I have noticed the following.
python-internals
About the changing id of an immutable string
Something about the id of objects of type str (in python 2.7) puzzles me. The str type is immutable, so I would expect that once it is created, it will always have the same id. I believe I don’t phrase myself so well, so instead I’ll post an example of input and output sequence.
How does swapping of members in tuples (a,b)=(b,a) work internally?
In [55]: a = 5 In [56]: b = 6 In [57]: (a, b) = (b, a) In [58]: a Out[58]: 6 In [59]: b Out[59]: 5 How does this swapping of values of a and b work internally? Its definitely not using a temp variable. Answers: Thank you for visiting the Q&A section on … Read more
When is del useful in Python?
I can’t really think of any reason why Python needs the del keyword (and most languages seem to not have a similar keyword). For instance, rather than deleting a variable, one could just assign None to it. And when deleting from a dictionary, a del method could be added.
Why does id({}) == id({}) and id([]) == id([]) in CPython?
Why does CPython (no clue about other Python implementations) have the following behavior?
‘order’ of unordered Python sets
I understand that sets in Python are unordered, but I’m curious about the ‘order’ they’re displayed in, as it seems to be consistent. They seem to be out-of-order in the same way every time:
About Python’s built in sort() method
What algorithm is the built in sort() method in Python using? Is it possible to have a look at the code for that method?
Are tuples more efficient than lists in Python?
Is there any performance difference between tuples and lists when it comes to instantiation and retrieval of elements?
Why can tuples contain mutable items?
If a tuple is immutable then why can it contain mutable items?
Why does a class’ body get executed at definition time?
In contrast to functions, a class’ body is executed at definition time: