Python split string based on conditional

Question

I want to split strings using a comma delimiter if the comma is preceded by a certain regex. Consider the case where my strings are in the format: \"(bunch of stuff that mig

Answer 1

You can use a positive look-behind if the FOO_REGEX is fixed-width. Here, you will get your line split after "$$asdf,"

See a sample working program:

import re    
str = 'hi, hello! $$asdf, I am foo, bar $$jkl, cool'
splts = re.split('(?<=\$\$asdf), *', str)
print splts

Output:

['hi, hello! $$asdf', 'I am foo, bar $$jkl, cool'] 

Answer 2

You could use re.findall instead of re.split.

>>> import re
>>> s = "hi, hello! $$asdf, I am foo, bar $$jkl, cool"
>>> [j for i in re.findall(r'(.*?\$\$[^,]*),\s*|(.+)', s) for j in i if j]
['hi, hello! $$asdf', 'I am foo, bar $$jkl', 'cool']

OR

Use external regex module to support variable length lookbehind since re won't support variable length look-behind assertions.

>>> import regex
>>> s = "hi, hello! $$asdf, I am foo, bar $$jkl, cool"
>>> regex.split(r'(?<=\$\$[^,]*),\s*', s)
['hi, hello! $$asdf', 'I am foo, bar $$jkl', 'cool']