Vfrdtyky

I have a string which looks like '-2--1' which means from -2 to -1 for my problem. I want to access both of these numbers from the string. str.split("-") won't work in this case. What are my options?

Edit: I can have a string like '2-5' as well, which means from 2 to 5 (In this case I need to extract 2 and 5) or a string like '-2-5' which means -2 to 5(-2 and 5 are the numbers of importance in this case).

If there is always going to be a double dash -- you could do this.

s = '-2--1'

s.replace('--',' -').split(' ') # ['-2', '-1']

import re

s = '-1--2'

result = [int(d) for d in re.findall(r'-?d+', s)]

You could use a regex to find all numbers.

>>> import re 

>>> re.findall(r'-?d+', '-2--1')

['-2', '-1']

This will work for any characters between numbers. e.g.

>>> re.findall(r'-?d+', '-2---$&234---1')

['-2', '234', '-1']

But it assumes a - before a number will make it negative, of course

Split on the hyphen that comes after a digit:

def splitrange(s):

    return re.split(r'(?<=d)-', s)

Demo:

>>> splitrange('-2--5')

['-2', '-5']

>>> splitrange('-2-5')

['-2', '5']

>>> splitrange('2-5')

['2', '5']

>>> splitrange('2--5')

['2', '-5']

split the numbers:

split= str.split('-')

Function to apply negations:

def actual(ns, minus=False):

    if not ns:

        return

    n, *rest = ns

    if n == '':

        yield from actual(rest, not minus)

        return

    yield -int(n) if minus else int(n)

    yield from actual(rest)

And now you can actualize:

numbers = list(actual(split))

It will also handle multiple negations....