Python 使用新行上的字符串拆分字符串

Question

I am trying to split a string with a word that is on a new line by itself.

For example, I want to split the string into parts whenever I encounter the word "SPLIT". For my use case the word "SPLIT" should only be all by itself on a new line:

I tried str.split("\nSPLIT") , but having trouble making it work for after the word.

Hello there,
SPLIT
how are you?

should return ["Hello there,", "how are you?"]

Hello there, SPLIT how are you?

should return ["Hello there, SPLIT how are you?"]

Hello there,
SPLIT

should return ["Hello there,", ""]

Hello there,
SPLIT how are you?

should return ["Hello there,\nSPLIT how are you?"]

Appreciate the help.

Answer 1

You can use

re.split(r'\n?^SPLIT$\n?', text, flags=re.M)
re.split(r'(?:^|\n)SPLIT(?:$|\n)', text)

See the Python demo .

The \n?^SPLIT$\n? regex used with re.M flag matches an optional newline char, then makes sure the index is at the start of a line ( ^ ) and then matches and consumes SPLIT and then checks if there is end of a line position right after SPLIT and then matches an optional newline char.

The (?:^|\n)SPLIT(?:$|\n) regex just matches either start of string or a newline, SPLIT and then either end of string or a newline char. Note the use of non-capturing groups so as to avoid having newlines or extra empty strings as part of the resulting list.

See the regex demo #1 and regex demo #2 .