For reasons that I won't explain, as they are too complicated
and not terribly relevant, I am interested in discovering what
people actually use regular expressions for. Not the subject
domain, but the construction of the regular expressions.
I know about computer scientists and parsing, and I know about
the use of relatively simple ones for things like extracting
HTML links from Web pages. But I don't have much feel for the
(probably rare but difficult) uses of more complex ones for
other purposes. I have heard of several such uses, but don't
have an overall idea of what is going on.
Any pointers appreciated, to more-or-less anything.
Regards,
Nick Maclaren.
14  1264 
Nick Maclaren <nm**@cus.cam.a c.ukwrote in comp.lang.perl. misc:
>
For reasons that I won't explain, as they are too complicated
and not terribly relevant,
Your reasons are relevant as a motivation for your readers to
answer such a broad question.
I am interested in discovering what
people actually use regular expressions for. Not the subject
domain, but the construction of the regular expressions.
How is the construction of a regex related to what it is used
for? That makes no sense.
I know about computer scientists and parsing,
That's a (broad) subject domain.
and I know about
the use of relatively simple ones for things like extracting
HTML links from Web pages.
That's another subject domain (and a regex for that purpose wouldn't
qualify as "relatively simple").
But I don't have much feel for the
(probably rare but difficult) uses of more complex ones for
other purposes. I have heard of several such uses, but don't
have an overall idea of what is going on.
Your question is so badly defined, it would take considerable effort
just to make sense of it. Given your premise of "Never mind what I
need it for, just gimme the info," I won't even try.
Anno
On 24 Aug 2007 10:58:46 GMT, nm**@cus.cam.ac .uk (Nick Maclaren) wrote:
>
For reasons that I won't explain, as they are too complicated
and not terribly relevant, I am interested in discovering what
people actually use regular expressions for. Not the subject
domain, but the construction of the regular expressions.
I know about computer scientists and parsing, and I know about
the use of relatively simple ones for things like extracting
HTML links from Web pages. But I don't have much feel for the
(probably rare but difficult) uses of more complex ones for
other purposes. I have heard of several such uses, but don't
have an overall idea of what is going on.
Any pointers appreciated, to more-or-less anything.
In the linked project, regular expression are used to parse
communication protocol responses, file contents, and interporocess
communcation (at least).
They may not be pretty elegant solutions, but this is the first
project I made in python (and also with regex)!!
NOTE: I am the author, and I swear the application is free of viruses,
it has been fully developed with a python and a WingWare standar
installation, and it will only deposit some files on your
$python$/Lib/site-packages folder.
Any comments welcome.
NOTE2: Software in spanish, but it should not be pretty difficult to
follow (I hope!)
best regards,
Zara http://www.albalaing.com/Firmware.aspx?id_firmware=2359
Nick,
In "Mastering Regular Expressions" by Jeffrey E. F. Friedl your
question is answered in the first 6 chapters. Seriously, that's what
it takes. It's a really good book.
Cheers
Bert
On Aug 24, 12:58 pm, n...@cus.cam.ac .uk (Nick Maclaren) wrote:
For reasons that I won't explain, as they are too complicated
and not terribly relevant, I am interested in discovering what
people actually use regular expressions for. Not the subject
domain, but the construction of the regular expressions.
I know about computer scientists and parsing, and I know about
the use of relatively simple ones for things like extracting
HTML links from Web pages. But I don't have much feel for the
(probably rare but difficult) uses of more complex ones for
other purposes. I have heard of several such uses, but don't
have an overall idea of what is going on.
Any pointers appreciated, to more-or-less anything.
Regards,
Nick Maclaren.
In article <fa**********@g emini.csx.cam.a c.uk>,
Nick Maclaren <nm**@cus.cam.a c.ukwrote:
>
For reasons that I won't explain, as they are too complicated
and not terribly relevant, I am interested in discovering what
people actually use regular expressions for. Not the subject
domain, but the construction of the regular expressions.
Your question as phrased makes no sense to me. For that matter, it isn't
even a question. ;-)
Side note: please don't cross-post between c.l.py and c.l.perl.* -- the
group cultures are different and it's too easy to start flamewars.
--
Aahz (aa**@pythoncra ft.com) <* http://www.pythoncraft.com/
"If you don't know what your program is supposed to do, you'd better not
start writing it." --Dijkstra
In article <fa**********@m lucom4.urz.uni-halle.de>,
Mirco Wahab <wa********@gmx .netwrites:
|>
|Using complex regular expressions is like tank destruction
|with contact charges glued on them. Only a few people
|will even survive the first "usage", but survivors will
|then eventually be able to destroy almost every tank with
|tremendous speed and precision.
I must remember that! It is nicely put.
|On business software projects, maintainability is a key
|prerequisite - after using complex regular expressions
|on business critical parts you are bound to involve
|very very expensive maintenance programmers ... :)
Yes :-) Even regular expression experts have major problems
ensuring that complicated ones match everything that they need
to and nothing that they don't. The same thing applies to
uses of the C preprocessor and many uses of Perl ....
|What exactly did you "hear" of several "uses"? Which
|application? Academia, Business, ...?
Mainly academic research, but that still covers many fields.
However, I am not and never have been a 'pure' academic, and
am as interested in other uses as in academic research.
Regards,
Nick Maclaren.
On 2007-08-24, Nick Maclaren <nm**@cus.cam.a c.ukwrote:
people actually use regular expressions for. Not the subject
domain, but the construction of the regular expressions.
This is easy.
I use RE for checking whether some input matches a certain pattern, and
optionally, to extract some special part from the text.
Albert
On Aug 24, 6:58 am, n...@cus.cam.ac .uk (Nick Maclaren) wrote:
I am interested in discovering what
people actually use regular expressions for.
Hmm - let's see. I tend to use regular expressions when I am writing
code that needs to search through output to find certain patterns. I
also use them to convert text in one format into another format. I
also frequently use them to validate input - if I need input to be all
alphabetics, or a properly formatted floating point number, etc.
Nick Maclaren wrote:
For reasons that I won't explain, as they are too complicated
and not terribly relevant, I am interested in discovering what
people actually use regular expressions for.
Finding credit card numbers in files...among other things: http://filebox.vt.edu/users/rtilley/public/find_ccns/ This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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