\b

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is equivalent to 
(?:(?<=\w)(?!\w)|(?<!\w)(?=\w))

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If you want to include "-" as a word character, just change \w to [\w-]. 

(?:(?<=[\w-])(?![\w-])|(?<![\w-])(?=[\w-]))

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All together, that gives 

my $my_slash_b = qr/(?:(?<=[\w-])(?![\w-])|(?<![\w-])(?=[\w-]))/;

/$my_slash_b$check$my_slash_b/

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But since you "know" that $check starts and ends with a word character, the above simplifies to 

/(?<![\w-])$check(?![\w-])/

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If you wanted to go further and count any non-whitepspace as word characters, you're left with 

my $my_slash_b = qr/(?:(?<=\S)(?!\S)|(?<!\S)(?=\S))/;

/$my_slash_b$check$my_slash_b/

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and thus 

/(?<!\S)$check(?!\S)/

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In reply to Re: Word boundary in regexp by ikegami
in thread Word boundary in regexp by Anonymous Monk

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