Where to use \b and \B in Regular expression? I'm a beginner to Pearl. So, I didn't get clear understanding.
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\b and \B are documented in Assertions in perlre. It is also discussed in perlretut, saying:

An anchor useful in basic regexps is the word anchor \b. This matches a boundary between a word character and a non-word character \w\W or \W\w: 
        $x = "Housecat catenates house and cat";
        $x =~ /cat/;    # matches cat in 'housecat'
        $x =~ /\bcat/;  # matches cat in 'catenates'
        $x =~ /cat\b/;  # matches cat in 'housecat'
        $x =~ /\bcat\b/;  # matches 'cat' at end of string

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Note in the last example, the end of the string is considered a word boundary.

In general, the most useful skill you can develop early in learning about Perl is navigating the documentation.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: Word boundaries by kennethk
in thread Word boundaries by sandyago

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