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Matching sequentially repeating parentheses with Python Regex

Basically I'm trying to find a series of sequential repetitive patterns using python with a regex:

(X[0-9]+)+

For example, enter the input line:

YYYX4X5Z3X2

Get a list of results:

["X4X5", "X2"]

However, I get instead:

["X5", "X2"]

I checked the regexpal on regexpal and confirmed that it is correct, due to the way python handles the "()" I cannot get the desired result. Can anyone advise?

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3 answers


Turn your capturing group into a non-capturing group, (?:...)

not ...

>>> import re
>>> re.findall(r'(?:X[0-9]+)+', 'YYYX4X5Z3X2')
['X4X5', 'X2']


Another example:

>>> re.findall(r'(?:X[0-9]+)+', 'YYYX4X5Z3X2Z4X6X7X8Z5X9')
['X4X5', 'X2', 'X6X7X8', 'X9']
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change your template this way

((?:X[0-9]+)+)


Demo

(               # Capturing Group (1)
  (?:           # Non Capturing Group
    X           # "X"
    [0-9]       # Character Class [0-9]
    +           # (one or more)(greedy)
  )             # End of Non Capturing Group
  +             # (one or more)(greedy)
)               # End of Capturing Group (1)
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You need to specify in the group not capturing (?:<pattern>)

for the first template:

((?:X[0-9]+)+)
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