docs: protected boolean addToPath(GP path, ST segment) {
  		if (this.pathFactory != null) {
  			return this.pathFactory.addToPath(path, segment);
  		}
  		assert path != null;
  		assert segment != null;
  		try {
  			return path.add(segment);
  		} catch (Throwable e) {
  			throw new IllegalStateException(e);
  		}
  	}