Override builtin list syntax in python

Question

I wanted to try and replace python's mutable datastructures with immutable ones (similar to clojure).

Subclassing the builtin list class works and you can override __builtin__.list but I haven't found any way of changing what builtin syntax refers to

__builtin__.list = ImmutableListClass

my_list = [1, 2, 3]
print type(my_list)

>>> <type 'list'>

Is there any way to change this behavior or is it hardcoded in the interpreter?

Disclaimer: I'm aware this should never be done in a serious project and it's purely for my own entertainment.

For entertainment purpose you can look up for `tuples` in python :), They are immutable by default and you won't need to override anything :P — ZdaR, Jan 28 '15 at 11:09
You could use a colections.UserList and override the methods — Padraic Cunningham, Jan 28 '15 at 18:01

score 0 · Accepted Answer · answered Jan 28 '15 at 11:11

0

You cant since these module are written in C, and hence have .so extensions. You can however try using forbidden fruit:

http://clarete.li/forbiddenfruit/

answered Jan 28 '15 at 11:11

Games Brainiac

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I accept this answer, because it seems that the only possibility is to use forbidden fruit to modify (instead of replace) the existing `list` type which is used by the `[1, 2, 3]` syntax. – felixbr Jan 30 '15 at 13:23

score -2 · Answer 2 · edited May 23 '17 at 11:51

-2

Yes, it is possible. This answer does something similar, albeit with dicts, so I imagine that it could be adapted. However, I'm far too frightened to try.

edited May 23 '17 at 11:51

Community

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answered Jan 28 '15 at 11:11

Tom

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Override builtin list syntax in python

2 Answers2