Re: [opensuse] regexp -- defference between \< and \b ?

Randall R Schulz wrote:
On Tuesday 29 April 2008 17:58, David C. Rankin wrote:
Listmates:

With regular expressions, what is the difference between \< and \b ?
The man page says:

Which man page? There are many, many programs and libraries that implement regular-expression matching, and REs are by no means singly defined. There are many grammars for notating them and many varieties of fundamental matching constructs.


Actually it comes from man grep. Specifically:

The Backslash Character and Special Expressions
The symbols \< and \> respectively match the empty string at the beginning and end of a word. The symbol \b matches the empty string at the edge of a word, and \B matches the empty string provided it's not at the edge of a word. The symbol \w is a synonym for [[:alnum:]] and \W is a synonym for [^[:alnum:]].


end. Boundaries are either. (Am I going too fast for you??)


Trying to digest BRE (basic RE), ERE (extended RE) and ARE (Advanced RE) in a couple of readings itself moves too fast for me ;-)


Personally, I prefer the old-style \< and \> but apparently they're a thing of the past.


Thanks for your help Randall!

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