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pythonregex-greedy

Re.compile search doesn't show the full string

In a text I'd like to find if the text contains the following string:

"http://p.thisistheurl.com/v/" after that anything until "jpg".

So this is the python code that I wrote:

asdf = 'http://p.thisistheurl.com/v/adzl25/4321567/543276123/865.jpg'

regex = re.compile(r'http://p.thisistheurl.com/v/(.)*jpg')

regex.search(asdf)

<_sre.SRE_Match object; span=(0, 60), match='http://p.thisistheurl.com/v/adzl25/4321567/543276'>

As you can see the result doesn't show the whole string with the "jpg". Why doesn't it work?

Solution

  • I don't think there's any guarantee that the characters displayed after match= are actually the complete contents of the string that got matched. It probably just cuts off after 50 characters or so.

    Looking at cpython's implementation of SRE_Match.__repr__, this is indeed the case: the 50R right there is the smoking gun.

    result = PyUnicode_FromFormat(
        "<%s object; span=(%d, %d), match=%.50R>",
        Py_TYPE(self)->tp_name,
self->mark[0], self->mark[1], group0);

    If you access the actual matched string, rather than inspect it from the match object's printed representation, it goes all the way to jpg:

    >>> import re
>>> asdf = 'http://p.thisistheurl.com/v/adzl25/4321567/543276123/865.jpg'
>>> regex = re.compile(r'http://p.thisistheurl.com/v/(.)*jpg')
>>> print(regex.search(asdf).group(0))
http://p.thisistheurl.com/v/adzl25/4321567/543276123/865.jpg