Do you mean 
$string =~ /$_/;
$string =~ /\b$_\b/;

[download]
or do you really mean 
$string =~ /\Q$_\E/;
$string =~ /\b\Q$_\E\b/;

[download]
As soon as your variable contains Metacharacters, they are not the same. See quotemeta, Quoting metacharacters.

#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: \b in Unicode regex by kennethk
in thread \b in Unicode regex by Arik123

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