You can rely on convention, and simply name things with an underscore as the first character of the sub's name (and put in a note to the fact). If anyone gets burned by using the private interface, it's their own fault.

A truly private option would be to stash coderefs in a lexically declared hash.

package Foo;

my %hidden = (
              bar => sub { print "Bar\n"; },
              ...
             );

sub something_public {
  my( $baz, $quux ) = @_;

  return $hidden{bar}->( $baz + 5, reverse $quux );
}

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In reply to Re: Visibility of Subroutines within modules, by Fletch
in thread Visibility of Subroutines within modules, by ceedee

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