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From: ram@zedat.fu-berlin.de (Stefan Ram)
Newsgroups: comp.lang.python,alt.fantasy
Subject: Re: Pythonic way to combine regular expressions?
Followup-To: comp.lang.python
Date: 26 Sep 2026 12:22:14 GMT
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Xref: csiph.com comp.lang.python:198080 alt.fantasy:686

Johann 'Myrkraverk' Oskarsson <johann@myrkraverk.invalid> wrote or quoted:
>Thank you.  I'm sure Kent Beck of /eXtreme Programming/ would be proud
>of this regular expression if he bothered to read comp.lang.python.

  That regular expression can be made more readable in Python
  using verbose regular expressions while still avoiding names
  and parentheses within the regular expression.

exp = re.compile(
  r"""
  ^ [+-]? [0-9]+ $                             # Integer (123, -45)
  |
  ^ [+-]? [0-9]+ \. [0-9]+ [eE] [+-]? [0-9]+ $ # Float with "E"
  |
  ^ [+-]? [0-9]+ \. [0-9]+ $                   # Float without "E"
  |
  ^ [+-]? \. [0-9]+ [eE] [+-]? [0-9]+ $        # Starts with ".", has E
  |
  ^ [+-]? \. [0-9]+ $                          # Starts with ".", no "E"
  |
  ^ [+-]? [0-9]+ \. [eE] [+-]? [0-9]+ $        # Ends with ".", has "E"
  |
  ^ [+-]? [0-9]+ \. $                          # Ends with ".", no "E"
  |
  ^ [+-]? [0-9]+ [eE] [+-]? [0-9]+ $           # No ".", but "E"
  """,
  re.VERBOSE,
)

Newsgroups: comp.lang.python,alt.fantasy
Followup-To: comp.lang.python