Split string by comma unless followed by a space or a '+'

Question

I'm trying to split an extremely long string by commas. I have two requirements, however:

the comma cannot be followed by a space
the comma cannot be followed by a '+' symbol

so for example, the input would be:
text = "hello,+how are you?,I am fine, thanks"

and the output of this is:
['hello,+how are you?', 'I am fine, thanks']

i.e. the only comma that seperated the values was the one that was not followed by a '+' or a space
I have managed requirement 1) as follows:
re.split(r',(?=[^s]+)',text)

I cannot figure out how to add requirement 2)

Ann Zen · Answer

I suggest you go with @HampusLarsson's answer, but I'd like to squeeze in an answer that doesn't use imported modules:
s = "hello,+how are you?,I am fine, thanks"

ind = [0]+[i for i,v in enumerate(s)
           if v == ',' and s[i+1] not in [' ','+']]

parts = [s[i:j].lstrip(',')
         for i,j in zip(ind, ind[1:]+[None])]

print(parts)

Output:
['hello,+how are you?', 'I am fine, thanks']

Hampus Larsson · Answer

The simplest solution is to only look for the pattern that you don't want, and exclude it altogether. You do that using negative-lookahead in regular-expression.
>>> text = "hello,+how are you?,I am fine, thanks"
>>> re.split(r',(?![+ ])', text)
['hello,+how are you?', 'I am fine, thanks']

This will match , unless it's followed either by a literal + or a space.

Pratyaksh Saini · Answer

Try this
re.split(r',(?=[^s +])',text)

Split string by comma unless followed by a space or a '+'

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