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Polyglot CheatSheet - Bytes

Updated: 2022-04-04

1 byte = 8-bit integer, in the range 0 to 255

Python

  • bytes is an immutable array of bytes (PyString)
  • bytearray is a mutable array of bytes (PyBytes)
  • memoryview is a bytes view on another object (PyMemory)

bytes literal: b'...'

  • str objects: hold character data
  • bytes objects: hold raw bytes

Indexing returns a integer:

>>> a = b'asdf'
>>> a
b'asdf'
>>> a[0]
97

while str returns a character:

>>> b = 'asdf'
>>> b
'asdf'
>>> b[0]
'a'
  • Assigning or comparing an object that is not an integer to an element causes a TypeError exception.
  • Assigning an element to a value outside the range 0 to 255 causes a ValueError exception.

string must comes with encoding

bytearray:

>>> a = bytearray("123", 'utf-8')
>>> a[0]
49
>>> a[1]
50

bytes:

>>> a = bytes('abc', 'utf-8')
>>> a
b'abc'