all Python 3Byte sequencesfunction

bytearray.index

bytearray — search

Like find, but raises ValueError if not found.

Syntax

ba.index(...)

Prefer index when a missing needle means the data is broken: it raises ValueError on the spot, whereas find's -1 tends to slip downstream and corrupt a slice. The argument may also be a plain int in range 0-255, which searches for that single byte — handy, since ba[i] already yields an int rather than bytes.

Examples

print(bytearray(b'banana').index(b'na'))   # → 2
print(bytearray(b'banana').index(ord('n')))   # → 2
print(bytearray(b'banana').index(b'na', 3))   # → 4
print(bytearray(b'banana').find(b'x'))   # → -1
print(bytearray(b'banana').index(b'x'))   # → ValueError

See also

Common errors

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