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Super Kai (Kazuya Ito)
Super Kai (Kazuya Ito)

Posted on • Edited on

join in Python

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*Memo for a string and byte string(bytes and bytearray) functions:

*Memo for a string and byte string(bytes and bytearray):

str.join() and bytes.join() or bytearray.join() can concatenate the zero or more characters and bytes of the string and byte string respectively with the zero or more characters and bytes of each string and byte string respectively of an iterable as shown below:

*Memo:

  • The 1st argument is iterable(Required-Type:Iterable(str for str.join() or Bytes-like object for bytes.join() and bytearray.join())):
    • Don't use iterable=.

<String>:

v = ['one', 'two', 'three', 'four']

print(''.join(v))
# onetwothreefour

print(' '.join(v))
# one two three four

print('  '.join(v))
# one  two  three  four

print('-'.join(v))
# one-two-three-four

print(' - '.join(v))
# one - two - three - four

print('<->'.join(v))
# one<->two<->three<->four
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v = ['', '', '', '']

print(''.join(v))
print(' '.join(v))
print('  '.join(v))
# Nothing

print('-'.join(v))
# ---

print(' - '.join(v))
#  -  -  - 

print('<->'.join(v))
# <-><-><->
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v = []

print('-'.join(v))
# Nothing
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v = [0, 12, 345, 6789]

print(''.join(map(str, v)))
print(''.join([str(num) for num in v]))
# 0123456789

print('-'.join(map(str, v)))
print('-'.join([str(num) for num in v]))
# 0-12-345-6789
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<Byte String>:

bytes:

v = [b'one', b'two', b'three', b'four']
v = [bytearray(b'one'), bytearray(b'two'),
     bytearray(b'three'), bytearray(b'four')]

print(b''.join(v))
# b'onetwothreefour'

print(b' '.join(v))
# b'one two three four'

print(b'  '.join(v))
# b'one  two  three  four'

print(b'-'.join(v))
# b'one-two-three-four'

print(b' - '.join(v))
# b'one - two - three - four'

print(b'<->'.join(v))
# b'one<->two<->three<->four'
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v = [b'', b'', b'', b'']
v = [bytearray(b''), bytearray(b''), bytearray(b''), bytearray(b'')]

print(b''.join(v))
# b''

print(b' '.join(v))
# b'   '

print(b'  '.join(v))
# b'      '

print(b'-'.join(v))
# b'---'

print(b' - '.join(v))
# b' -  -  - '

print(b'<->'.join(v))
# b'<-><-><->'
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v = []

print(b'-'.join(v))
# b''
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v = [2, 4, 6]

print(b''.join(map(bytes, v)))
print(b''.join(map(bytearray, v)))
print(b''.join([bytes(num) for num in v]))
print(b''.join([bytearray(num) for num in v]))
# b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'

print(b'-'.join(map(bytes, v)))
print(b'-'.join(map(bytearray, v)))
print(b'-'.join([bytes(num) for num in v]))
print(b'-'.join([bytearray(num) for num in v]))
# b'\x00\x00-\x00\x00\x00\x00-\x00\x00\x00\x00\x00\x00'
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bytearray:

v = [b'one', b'two', b'three', b'four']
v = [bytearray(b'one'), bytearray(b'two'),
     bytearray(b'three') ,bytearray(b'four')]

print(bytearray(b'').join(v))
# bytearray(b'onetwothreefour')

print(bytearray(b' ').join(v))
# bytearray(b'one two three four')

print(bytearray(b'  ').join(v))
# bytearray(b'one  two  three  four')

print(bytearray(b'-').join(v))
# bytearray(b'one-two-three-four')

print(bytearray(b' - ').join(v))
# bytearray(b'one - two - three - four')

print(bytearray(b'<->').join(v))
# bytearray(b'one<->two<->three<->four')
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v = [b'', b'', b'', b'']
v = [bytearray(b''), bytearray(b''), bytearray(b''), bytearray(b'')]

print(bytearray(b'').join(v))
# bytearray(b'')

print(bytearray(b' ').join(v))
# bytearray(b'   ')

print(bytearray(b'  ').join(v))
# bytearray(b'      ')

print(bytearray(b'-').join(v))
# bytearray(b'---')

print(bytearray(b' - ').join(v))
# bytearray(b' -  -  - ')

print(bytearray(b'<->').join(v))
# bytearray(b'<-><-><->')
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v = []

print(bytearray(b'-').join(v))
# bytearray(b'')
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v = [2, 4, 6]

print(bytearray(b'').join(map(bytes, v)))
print(bytearray(b'').join(map(bytearray, v)))
print(bytearray(b'').join([bytes(num) for num in v]))
print(bytearray(b'').join([bytearray(num) for num in v]))
# bytearray(b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')

print(bytearray(b'-').join(map(bytes, v)))
print(bytearray(b'-').join(map(bytearray, v)))
print(bytearray(b'-').join([bytes(num) for num in v]))
print(bytearray(b'-').join([bytearray(num) for num in v]))
# bytearray(b'\x00\x00-\x00\x00\x00\x00-\x00\x00\x00\x00\x00\x00')
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