Bug. An even simpler case: 
    "-" =~ /\s*\p{Dash}/;

[download]
This fails. Removing the \s* or adding {1} after the \p{Dash} makes it succeed.

Please use perlbug to file a bug report.

In reply to Re: Strange re behaviour for /\s*\p{Dash}\s*/ - bug or feature? by JavaFan
in thread Strange re behaviour for /\s*\p{Dash}\s*/ - bug or feature? by Anonymous Monk

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