Splitting on last delimiter in Python string?

Edge Case Handling

Going fast and furious with rsplit()? Don't crash into the edge cases!

• No Delimiter Way Out: When your text turns into a desert with no Oases (read delimiters), rsplit() turns the mirage into a list with your string as a lone wanderer, sound and safe:

text = "abc"
# Oops! No oasis in sight 🏜️
parts = text.rsplit(',', 1)  # ['abc']
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• The Delimiter Cliff: Hit the end of the world with a delimiter at the very end? Get ready for an empty string free fall:

text = "a,b,c,"
# cliffhanger delimiter at the end!
before, after = text.rsplit(',', 1)
print(after == '')  # True, it's a void!
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For such tricky terrains, use a custom lifeguard function to carefully bring down the trailing delimiter.

Missile Missing In Action?

Struggling with MIA (Missing-In-Action) delimiters? str.rpartition() to the rescue! This crafty function hands you a 3-piece tuple goodie bag with everything before, the delimiter and everything after, no strings attached!

text = "a,b,c"
# Checking the missing and the found
before, delimiter, after = text.rpartition(',')
print(before)  # 'a,b'
print(after)   # 'c'
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Even when the delimiter goes AWOL, rpartition() provides for the missing with an empty string as the guard of the first position.

Tail Delimiter Surgery

Got a tail delimiter blocking your way? Cut it off with a custom surgical procedure!

def split_last_delimiter(text, delimiter):
  # Detect and remove tailblock
  if text.endswith(delimiter):
    text = text[:-len(delimiter)]
  # Regular split after surgery
  return text.rsplit(delimiter, 1)
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This incorporates a pre-check for trailing delimiter and smartly schedules it for surgery before the split.

Reversals: Handle with Care!

str[::-1] pulling you with its charm? Watch out for the landmines of Unicode and multi-byte characters that could blow up! For safe traversal from the string's end, rsplit() and rpartition() are your trusty landmine detectors.