ps2.lino

define atype {
   number n;
   param number p;
   constraints { n * p = 1; }
}

define btype {
   atype a(p = 3);
   draw { &draw_btype; }
}

__END__

sub draw_btype {
  my $env = shift;
  print STDERR qq{*** n = $env->{"a.n"}\n};
}