Looping through python regex matches

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This has to be easier than what I am running into. My problem is turning a string that looks like this:

ABC12DEF3G56HIJ7

into

12 * ABC
3  * DEF
56 * G
7  * HIJ

And I can’t, for the life of me, design a correct set of loops using REGEX matching. The crux of the issue is that the code has to be completely general because I cannot assume how long the [A-Z] fragments will be, nor how long the [0-9] fragments will be.

Thank you for any assistance!

Python’s re.findall should work for you.

Live demo

import re

s = "ABC12DEF3G56HIJ7"
pattern = re.compile(r'([A-Z]+)([0-9]+)')

for (letters, numbers) in re.findall(pattern, s):
    print(numbers, '*', letters)

It is better to use re.finditer if your dataset is large because that reduces memory consumption (findall() return a list of all results, finditer() finds them one by one).

import re

s = "ABC12DEF3G56HIJ7"
pattern = re.compile(r'([A-Z]+)([0-9]+)')

for m in re.finditer(pattern, s):
    print m.group(2), '*', m.group(1)


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