You can't parse [X]HTML with regex. Because HTML can't be parsed by regex. Regex is not a tool that can be used to correctly parse HTML. As I have answered in HTML-and-regex questions here so many times before, the use of regex will not allow you to consume HTML. Regular expressions are a tool that is insufficiently sophisticated to understand the constructs employed by HTML. HTML is not a regular language and hence cannot be parsed by regular expressions. Regex queries are not equipped to break down HTML into its meaningful parts. so many times but it is not getting to me. Even enhanced irregular regular expressions as used by Perl are not up to the task of parsing HTML. You will never make me crack. HTML is a language of sufficient complexity that it cannot be parsed by regular expressions. Even Jon Skeet cannot parse HTML using regular expressions. Every time you attempt to parse HTML with regular expressions, the unholy child weeps the blood of virgins, and Russian hackers pwn your webapp. Parsing HTML with regex summons tainted souls into the realm of the living. HTML and regex go together like love, marriage, and ritual infanticide. The <center> cannot hold it is too late. The force of regex and HTML together in the same conceptual space will destroy your mind like so much watery putty. If you parse HTML with regex you are giving in to Them and their blasphemous ways which doom us all to inhuman toil for the One whose Name cannot be expressed in the Basic Multilingual Plane, he comes. HTML-plus-regexp will liquify the nerves of the sentient whilst you observe, your psyche withering in the onslaught of horror. Rege̿̔̉x-based HTML parsers are the cancer that is killing StackOverflow it is too late it is too late we cannot be saved the trangession of a chi͡ld ensures regex will consume all living tissue (except for HTML which it cannot, as previously prophesied) dear lord help us how can anyone survive this scourge using regex to parse HTML has doomed humanity to an eternity of dread torture and security holes using regex as a tool to process HTML establishes a breach between this world and the dread realm of c͒ͪo͛ͫrrupt entities (like SGML entities, but more corrupt) a mere glimpse of the world of regex parsers for HTML will instantly transport a programmer's consciousness into a world of ceaseless screaming, he comes
, the pestilent slithy regex-infection will devour your HTML parser, application and existence for all time like Visual Basic only worse he comes he comes do not fight he com̡e̶s, ̕h̵is un̨ho͞ly radiańcé destro҉ying all enli̍̈́̂̈́ghtenment, HTML tags lea͠ki̧n͘g fr̶ǫm ̡yo͟ur eye͢s̸ ̛l̕ik͏e liquid pain, the song of re̸gular expre ssion parsingwill extinguish the voices of mortal man from the sphere I can see it can you see ̲͚̖͔̙î̩́t̲͎̩̱͔́̋̀ it is beautiful the f
inal snuffing of the lies of Man ALL IS LOŚ͖̩͇̗̪̏̈́T ALL IS LOST the pon̷y he comes he c̶̮om
es he co mes the ichor permeates all MY FACE MY FACE ᵒh god no NO NOO̼OO NΘ stop the an*̶͑̾̾̅ͫ͏̙̤g͇̫͛͆̾ͫ̑͆l͖͉̗̩̳̟̍ͫͥͨe̠̅s
͎a̧͈͖r̽̾̈́͒͑enot rè̑ͧ̌aͨl̘̝̙̃ͤ͂̾̆ ZA̡͊͠͝LGΌ ISͮ̂҉̯͈͕̹̘̱ TO͇̹̺ͅƝ̴ȳ̳ TH̘Ë͖́̉ ͠P̯͍̭O̚N̐Y̡ H̸̡̪̯ͨ͊̽̅̾̎Ȩ̬̩̾͛ͪ̈́̀́͘ ̶̧̨̱̹̭̯ͧ̾ͬC̷̙̲̝͖ͭ̏ͥͮ͟Oͮ͏̮̪̝͍M̲̖͊̒ͪͩͬ̚̚͜Ȇ̴̟̟͙̞ͩ͌͝S̨̥̫͎̭ͯ̿̔̀ͅ
You doom us all to inhuman toil for the One whose Name cannot be expressed in the Basic Multilingual Plane.
RegEx match open tags except XHTML self-contained tags:
Ah, yes. I've thrown that into that text to movie thing a while ago. It came out relatively well.
You can, actually, with Oniguruma, a regexp library present in, for example, Ruby. Check the manual sections 8 "Back reference" and 9 "Subexp call ("Tanaka Akira special")" for details and examples; and yes, these regexen are actually Turing-complete.
Also, parsing a string of maybe 200 characters may very well take from several seconds up to several minutes, but that's a minor detail.
You don't have to cross the pacific for backreferences and subexpression, zotov.
PCRE library does those evil spells since... pfft, 5, 8 years? Something like that.
Then those ain't really regexes, the parsing really isn't practical... and so on.
Old schoolers just say NO to stuff that will break, the faceless C# crowd doesn't really never ever question the meaning of things, and noobs want to regex-parse the world constantly. twice.
This prose kind of makes them all march to the beat of single drum, uses music ligatures, and goes very Great Old Ones over everybody's hesitations. Which is always a plus.
Not everyone is going to enroll in the cult of Regextotep, great suffering is required to unleash the Knowledge.
My theory is that regex mistakes are the modern equivalent of union bargaining, keeping code-monkey prices up using stupid mistakes that managers are incapable of understanding. (Shhh.)
Related is the smaller issue - hey can't we match all valid URLs/domains with a regex? If you are on Android then you can. (Scary)
We also have jwz's code for extracting a name from an email address header which is a bunch of lisp wrapped around regexes.
Some people, when presented with a problem, think to themselves "I know- I'll invoke the faceless old ones. Now they have two problems"
Wow, what timing. After one too many cascading... "issues"... in setting up various new packages on my server, I wrote this, in obvious tribute to that wonderful post.
original (warning: home ADSL)
The stackoverflow post is better and more subtle, but... meh. It was late and bugs had already fried my sanity.
what are all the pretty characters at the end? an S with MAJESTY (trogdor style)? An A weilding a cutlass overhead? An H that had some sort of fight with a paint brush & a ladder??
Android renders that last bit surprisingly badly. I wonder if it's a font problem our if the browser is really that bad.