To answer your question: the boundary character is a zero-width assertion like (?:(?=\w)(?<=\W)|(?=\W)(?<=\w)) (next char is word and prev is non-word, or vice-versa). If you want a different definition of a boundary, you would need to roll your own boundary expression.
Caution: Contents may have been coded under pressure.

In reply to Re: Regexp dashes at boundaries by Roy Johnson
in thread Regexp dashes at boundaries by cormanaz

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