Simple custom Unity references with caching

SimpleExtension.cs

using UnityEngine;
using System.Collections;

public class NaxBehaviour : MonoBehaviour
{
	private PathFinder _pathFinder;

	public PathFinder pathFinder
	{
		get
		{
			if (_pathFinder == null)
			{
				PathFinder finder = GetComponent<PathFinder>();
				this.pathFinder = finder;
			}

			return this._pathFinder;
		}
		set
		{
			this._pathFinder = value;
			SendMessage("SetPathFinder", _pathFinder, SendMessageOptions.DontRequireReceiver);
		}
	}

	private void SetPathFinder(PathFinder finder)
	{
		this._pathFinder = pathFinder;
	}
}