How do i make something fall only if the "player" is withing a range?

so i making an object fall from the roof only when you the player get to specific amount of distance from the object
this is what i have, what can i fix?

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
// Use this for initialization

public class FallWhenNearPlayer : MonoBehaviour
{
public Transform other;

public float killRange { get; private set; }

void Example()
{
    if (other)
    {
        killRange = 5.0F;
        float dist = Vector3.Distance(other.position, transform.position);
        if (other.position - transform.position = 20)
        {
            GetComponent<Rigidbody>().useGravity = true;
        }
    }
}

}

Use OnTriggerEnter with the corresponding functionality you want the falling object to have.

I am not entirely certain here, but shouldn’t you have == in your last if, else you are assigning 20 to transform.position?

This is one method. Start by adding a RigidBody to all the objects you want to have fall. Disable the useGravity boolean so it floats.

Then add the following script to your Player:

float radius = 5; // 5 meter radius around player

void LateUpdate () {
  RaycastHit[] hits = SphereCastAll ( transform.position, radius, Vector3.up, maxDistance = 0.001f );

 foreach (RaycastHit hit in hits) {
  try {
    hit.gameObject.GetComponent<RigidBody> ().usingGravity = true;
   }
  catch (Exception E) {} // have to add: using System; at the top of the script
}
}