1.13. Simultaneous Assignment

Simultaneous (tuple) assignment lets you assign values to multiple variables in a single statement. It is especially handy for swapping variables without a temporary placeholder.

Traditional swap:

temp = x
x = y
y = temp

Concise swap with simultaneous assignment:

x, y = y, x

More examples:

• Multiple assignments: a, b, c = 1, 2, 3

• Unpacking iterables: x, y = [10, 20]

• Ignoring values with a throwaway name: first, _ = (5, 6)

• Extended unpacking: head, *middle, tail = [1, 2, 3, 4, 5] # head=1, middle=[2,3,4], tail=5

Notes:

• The right-hand side is fully evaluated before any assignments occur.

• The number of targets must match the number of values (unless using starred unpacking).