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From: "Peter J. Holzer" <hjp-python@hjp.at>
Newsgroups: comp.lang.python
Subject: Re: Correct syntax for pathological re.search()
Date: Sat, 12 Oct 2024 12:59:58 +0200
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On 2024-10-11 17:13:07 -0400, AVI GROSS via Python-list wrote:
> Is there some utility function out there that can be called to show what =
the
> regular expression you typed in will look like by the time it is ready to=
 be
> used?

I assume that by "ready to be used" you mean the compiled form?

No, there doesn't seem to be a way to dump that. You can

    p =3D re.compile("\\\\sout{")
    print(p.pattern)

but that just prints the input string, which you could do without
compiling it first.

But - without having looked at the implementation - it's far from clear
that the compiled form would be useful to the user. It's probably some
kind of state machine, and a large table of state transitions isn't very
readable.

There are a number of websites which visualize regular expressions.
Those are probably better for debugging a regular expression than
anything the re module could reasonably produce (although with the
caveat that such a web site would use a different implementation and
therefore might produce different results).

        hp

--=20
   _  | Peter J. Holzer    | Story must make more sense than reality.
|_|_) |                    |
| |   | hjp@hjp.at         |    -- Charles Stross, "Creative writing
__/   | http://www.hjp.at/ |       challenge!"

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