For example, see this old commit setting the WebKit maximum nesting depth to 2048. I am told it is 512 by default today. https://www.mail-archive.com/webkit-cha

For example, see this old commit setting the WebKit maximum nesting depth to 2048. I am told it is 512 by default today. https://www.mail-archive.com/webkit-changes@lists.webkit.org/msg02599.html https://www.mail-archive.com/webkit-changes@lists.webkit.org... I'm fairly certain all browsers will impose such a limit or risk blowing their stack and crashing. Turns out there are advantages to setting upper bounds after all. Who'da thunk? Regarding the BDD approach, it looks like somebody already implements it with excellent performance and memory characteristics: http://www.cs.rutgers.edu/~vinodg/papers/raid2010/raid2010_slides.pps http://www.cs.rutgers.edu/~vinodg/papers/raid2010/raid2010_s... Of course, the point (if you read back) was not to say that you should use REs for all parsing. Just merely to correct a commonly repeated mistake that 'REs cannot parse HTML'. They can do so just fine.