rfind in Python

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*Memo:

• My post explains string, bytes and bytearray functions.

str.rfind() and bytes.rfind() or bytearray.rfind() can respectively get the last index of the substring and byte substring matched to sub in the range [start, end) (without error even if the substring and byte substring don't exist respectively) as shown below:

*Memo:

• The 1st argument is sub(Required-Type:str for str.rfind() or Bytes-like object and int for bytes.rfind() and bytearray.rfind()):
  • It's the substring and byte substring of zero or more characters and bytes respectively.
  • Don't use sub=.
• The 2nd argument is start(Optional-Default:None-Type:int/NoneType):
  • It's a start index.
  • If it's None, the 1st index is set.
  • Don't use start.
• The 3rd argument is end(Optional-Default:None-Type:int/NoneType):
  • It's an end index.
  • If it's None, the string and bytes or bytearray length are set to it respectively.
  • Don't use end.
• -1 is returned if sub doesn't exist.
• start and end can be signed indices(zero and positive and negative indices).
• Error doesn't occur even if [start, end) is out of the range [The 1st index, The string and bytes or bytearray length).

<String>:

v = 'grapes peach'

print(v.rfind('pe'))             # 7
print(v.rfind('pe', None, None)) # 7
print(v.rfind('pe', -100, 100))  # 7
print(v.rfind('pe', 3))          # 7
print(v.rfind('pe', -9))         # 7
print(v.rfind('pe', 4))          # 7
print(v.rfind('pe', -8))         # 7
print(v.rfind('pe', 7))          # 7
print(v.rfind('pe', -5))         # 7
print(v.rfind('pe', 0, 5))       # 3
print(v.rfind('pe', -12, -7))    # 3
print(v.rfind('pe', 7, 12))      # 7
print(v.rfind('pe', -5, 12))     # 7

print(v.rfind(''))            # 12
print(v.rfind('g', 0, 1))     # 0
print(v.rfind('g', -12, -11)) # 0
print(v.rfind('h', 11, 12))   # 11
print(v.rfind('h', -1, 12))   # 11

print(v.rfind('PE'))          # -1
print(v.rfind('pe', 8))       # -1
print(v.rfind('pe', -4))      # -1
print(v.rfind('pe', 0, 4))    # -1
print(v.rfind('pe', -12, -8)) # -1
print(v.rfind('pe', 8, 12))   # -1
print(v.rfind('pe', -4, 12))  # -1
print(v.rfind('abc'))         # -1

v = ''

print(v.rfind('')) # 0

<Bytes & Bytearray>:

v = b'grapes peach'
v = bytearray(b'grapes peach')

print(v.rfind(b'pe'))                        # 7
print(v.rfind(bytearray(b'pe')))             # 7
print(v.rfind(b'pe', None, None))            # 7
print(v.rfind(bytearray(b'pe'), None, None)) # 7
print(v.rfind(b'pe', -100, 100))             # 7
print(v.rfind(bytearray(b'pe'), -100, 100))  # 7
print(v.rfind(b'pe', 3))                     # 7
print(v.rfind(bytearray(b'pe'), 3))          # 7
print(v.rfind(b'pe', -9))                    # 7
print(v.rfind(bytearray(b'pe'), -9))         # 7
print(v.rfind(b'pe', 4))                     # 7
print(v.rfind(bytearray(b'pe'), 4))          # 7
print(v.rfind(b'pe', -8))                    # 7
print(v.rfind(bytearray(b'pe'), -8))         # 7
print(v.rfind(b'pe', 7))                     # 7
print(v.rfind(bytearray(b'pe'), 7))          # 7
print(v.rfind(b'pe', -5))                    # 7
print(v.rfind(bytearray(b'pe'), -5))         # 7
print(v.rfind(b'pe', 0, 5))                  # 3
print(v.rfind(bytearray(b'pe'), 0, 5))       # 3
print(v.rfind(b'pe', -12, -7))               # 3
print(v.rfind(bytearray(b'pe'), -12, -7))    # 3
print(v.rfind(b'pe', 7, 12))                 # 7
print(v.rfind(bytearray(b'pe'), 7, 12))      # 7
print(v.rfind(b'pe', -5, 12))                # 7
print(v.rfind(bytearray(b'pe'), -5, 12))     # 7

print(v.rfind(b''))                       # 12
print(v.rfind(bytearray(b'')))            # 12
print(v.rfind(b'g', 0, 1))                # 0
print(v.rfind(bytearray(b'g'), 0, 1))     # 0
print(v.rfind(ord('g'), 0, 1))            # 0
print(v.rfind(103, 0, 1))                 # 0
print(v.rfind(b'g', -12, -11))            # 0
print(v.rfind(bytearray(b'g'), -12, -11)) # 0
print(v.rfind(ord('g'), -12, -11))        # 0
print(v.rfind(103, -12, -11))             # 0
print(v.rfind(b'h', 11, 12))              # 11
print(v.rfind(bytearray(b'h'), 11, 12))   # 11
print(v.rfind(ord('h'), 11, 12))          # 11
print(v.rfind(104, 11, 12))               # 11
print(v.rfind(b'h', -1, 12))              # 11
print(v.rfind(bytearray(b'h'), -1, 12))   # 11
print(v.rfind(ord('h'), -1, 12))          # 11
print(v.rfind(104, -1, 12))               # 11

print(v.rfind(b'PE'))                     # -1
print(v.rfind(bytearray(b'PE')))          # -1
print(v.rfind(b'pe', 8))                  # -1
print(v.rfind(bytearray(b'pe'), 8))       # -1
print(v.rfind(b'pe', -4))                 # -1
print(v.rfind(bytearray(b'pe'), -4))      # -1
print(v.rfind(b'pe', 0, 4))               # -1
print(v.rfind(bytearray(b'pe'), 0, 4))    # -1
print(v.rfind(b'pe', -12, -8))            # -1
print(v.rfind(bytearray(b'pe'), -12, -8)) # -1
print(v.rfind(b'pe', 8, 12))              # -1
print(v.rfind(bytearray(b'pe'), 8, 12))   # -1
print(v.rfind(b'pe', -4, 12))             # -1
print(v.rfind(bytearray(b'pe'), -4, 12))  # -1
print(v.rfind(b'abc'))                    # -1
print(v.rfind(bytearray(b'abc')))         # -1

v = b''
v = bytearray(b'')

print(v.rfind(b''))            # 0
print(v.rfind(bytearray(b''))) # 0