regex to split on pipe character except when in square brackets

Question

As the title suggest, I would like to split values on the |character except when the | character is nested in brackets [|] .

For example, taking the text of:

H3609|E1.7|E1.3|D09[7|9]

where I would like to split out ["H3609", "E1.7", "E1.3", "D09[7|9]"]

So far I have tried something very basic like: [A-z0-9\.]* would get back (assuming python using re. findall() )

["H3609", "E1.7", "E1.3", "D09[7", "9]"]

any suggestions?

Thanks in advance!

Answer 1

You can use

re.findall(r'(?:\[[^][]*]|[^][|])+', text)

See the regex demo .

Details :

• (?: - start of a non-capturing group that groups two patterns:
  • \[[^][]*] - a [ , then any zero or more chars other than [ and ] and then a ] char
  • | - or
  • [^][|] - any char but ] , [ and |
• )+ - repeat matching the group patterns one or more times.

See a Python demo :

import re
text = 'H3609|E1.7|E1.3|D09[7|9]'
print( re.findall(r'(?:\[[^][]*]|[^][|])+', text) )
# => ['H3609', 'E1.7', 'E1.3', 'D09[7|9]']