works1.lino

define point {
  number x, y;
  draw { &draw_point; } 
}

define line {
  point start, end;
  draw { &draw_line; } 
}

point P, Q;
line A, B;

constraints {
  A + (2,3) = B;
  P + (4,5) = Q;
  Q = (10, 14);
}

__END__

sub draw_line { 
  my $env = shift;
  my $s = hash2str($env->var_hash);
  print "DRAWING LINE ($s)\n";
}

sub draw_point {
  my $env = shift;
  my $s = hash2str($env->var_hash);
  print "DRAWING POINT ($s)\n";
}