Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Chris Angelico <rosuav@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Screen scraper to get all 'a title' elements
Date: Thu, 26 Nov 2015 10:54:04 +1100
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On Thu, Nov 26, 2015 at 10:44 AM, Grobu <snailcoder@retrosite.invalid> wrote:
> On 26/11/15 00:06, Chris Angelico wrote:
>>
>> On Thu, Nov 26, 2015 at 9:48 AM, ryguy7272 <ryanshuell@gmail.com> wrote:
>>>
>>> Thanks!!  Is that regex?  Can you explain exactly what it is doing?
>>> Also, it seems to pick up a lot more than just the list I wanted, but
>>> that's ok, I can see why it does that.
>>>
>>> Can you just please explain what it's doing???
>>
>>
>> It's a trap!
>>
>> Don't use a regex to parse HTML, unless you're deliberately trying to
>> entice young and innocent programmers to the dark side.
>>
>> ChrisA
>>
>
> Sorry, I wasn't aware of regex being on the dark side :-)
> Now that you mention it, I suppose that their being complex and
> error-inducing could lead to broken code all too easily when there is a
> reliable, ready-made solution like BeautifulSoup.

Regular expressions have their uses, but parsing HTML is not one of
them. The most important use of a regex is letting an end user control
the search pattern; it's a compact language for describing a variety
of text search concepts. For hard-coded regular expressions, there are
some places where they're very good, and a lot of places where they're
the wrong tool for the job. And one of those wrong-tool-for-job places
is parsing stuff that fundamentally cannot be parsed with regexes,
such as HTML. You _need_ a proper parser, which is what Beautiful Soup
is for.

ChrisA