From: "David A. Black" <dblack@...>
Date: 2009-07-15T22:07:40+09:00
Subject: Re: Search in string with regular expression

Hi --

On Wed, 15 Jul 2009, Robert Dober wrote:

> On 7/15/09, Harry Kakueki <list.push@gmail.com> wrote:
>>> Maybe
>>>  str2 = str1.scan( /\bfrog\w*\B/ ).join(" ")
>>> that is if you want to match frog at the start of words only (\b) and
>>> assure charcters of your choice up to the end of the word? As \w might
>>> be a little bit too permissive, in 1.9 you might prefer
>>>   str2 = str1.scan( /\bfrog[[:alpha:]]*\B/ ).join(" ")
>>> and all those nice variations ;)
>>>
>>> HTH
>>> Robert
>>>
>>>
>>>
>> Or maybe, :)
>>
>> str2 = str1.scan( /\bfrog\w*\b/ ).join(" ")
> No it was not a typo, I thought that \B was matching at the end of the
> word, I did not test with a frog at the end.
> I stand corrected \B does not have a special meaning and \b is just a
> word boundary.

\B is the opposite of \b, i.e., "not at a word boundary". So:

   >> /\B./.match("word")[0]
   => "o"


David

-- 
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