all Python 3Byte sequencesfunction

bytes.join

bytes — split and join

Join a sequence of bytes with this separator.

Syntax

b.join(...)

Every item must be bytes-like — a list of ints or of str raises TypeError. That is the usual trap: iterating over bytes yields ints, so b'-'.join(b'abc') fails instead of producing b'a-b-c'. The separator decides the result type (bytes.join returns bytes even for bytearray items), and joining once is far cheaper than repeated += in a loop.

Examples

print(b'-'.join([b'a', b'b', b'c']))   # → b'a-b-c'
print(b''.join([b'ab', b'cd']))   # → b'abcd'
print(b'+'.join(b'a-b-c'.split(b'-')))   # → b'a+b+c'
print(b'-'.join([bytearray(b'x'), b'y']))   # → b'x-y'
print(b', '.join([]))   # → b''
print(b'-'.join([b'a', 'b']))   # → TypeError

See also

Common errors

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