http://www.perlmonks.org?node_id=1027740


in reply to What does 'global' (/g) do in a regexp in this particular case?

That case is a bug

See https://rt.perl.org/rt3//Public/Search/Simple.html?q=/g%20pos

If you add  scalar in front of the match, it will match regardless of //g

If you use single pair of parens  if( ) its like scalar context

Tutorials: Context in Perl: Context tutorial, "List" Is a Four-Letter Word, Easy Reference for Contexts, Mini-Tutorial: Scalar vs List Assignment Operator