code: func orMorphism(p *Path) morphism {
  	return morphism{
  		Reversal: func(ctx *pathContext) (morphism, *pathContext) { return orMorphism(p), ctx },
  		Apply: func(in shape.Shape, ctx *pathContext) (shape.Shape, *pathContext) {
  			return shape.Union{in, p.Shape()}, ctx
  		},
  	}
  }
docs: // orMorphism is the union, vice intersection, of a path and the current iterator.