sub f {
   'xxx' =~ /(.*)/;
   print("$_[0]\n");
}

'aaa' =~ /(.*)/;  f($1);    # xxx
'aaa' =~ /(.*)/;  f("$1");  # aaa

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Perl passes arguments by reference, not by value. You are passing a global variable, and the global variable gets changed the by the called function before the argument is used. Passing a copy of the global avoids the problem.

In reply to Re: a MooseX Q that's driving me up the wall :) by ikegami
in thread a MooseX Q that's driving me up the wall :) by tj_thompson

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