Are python int's architecture specific?

Question

We can define variables as integer values, e.g.

x = 3
y = -2

and then operate on bits with binary operators &, |, ^ and ~. The question is if we always get the same result on every architecture, or is the behavior architecture specific? Can we always assume a two's complement representation of integers?

Answer 1

Python 2.x supports two integer types: int and long. int is based on the underlying C long type and long is an arbitrary precision type. Very early version of Python (pre-2.2), treated the types as two separate types but they were mostly combined in Python 2.2. Python 3.x only uses the arbitrary precision type.

Bit operations behave as if applied to arbitrary-precision 2's complement numbers. If required, an int will be automatically promoted to a long in Python 2.x.

The behavior is consistent across platforms.