BCE0048: Type 'UnityEngine.Component' does not support slicing.

Im getting this error with this part of the code

  if(hasAnimation) animation["walk"].speed = 2;
  if(hasAnimation) animation["run"].speed = 3;

Here is the full code

 var mainCamera : GameObject; 
 
  var mainCameraScript; 
 
  var hasAnimation : boolean; 
 
  var isMoving : boolean;
 
  private var walkSpeed : float = 1.0;
 
  private var gravity = 100.0;
 
 private var moveDirection : Vector3 = Vector3.zero;
 
 private var charController : CharacterController;
 
 
 ///////////////////////////////////////////////////////////////
 // FUNCTION :: Start ////////////////////////////////////////
 ///////////////////////////////////////////////////////////////
 
 function Start(){
  charController = GetComponent(CharacterController);
  if(hasAnimation) animation.wrapMode = WrapMode.Loop;
  mainCameraScript = mainCamera.GetComponent("controller_camera");
  
  print (mainCamera);
  print (mainCameraScript);
  
  // set animation clip speeds
  if(hasAnimation) animation["walk"].speed = 2;
  if(hasAnimation) animation["run"].speed = 3;
 // if(hasAnimation) animation["attack"].speed = 1;
 }
 
 ////////////////////////////////////////////////////////
 // FUNCTION :: Update ////////////////////////////////
 ////////////////////////////////////////////////////////
 
 function Update(){
 
  // make sure the character is in contact with the ground
  if(charController.isGrounded == true){
   
   /////////////////////////////////////
   // set which animation clip is playing //
   /////////////////////////////////////
   
   if(Input.GetButton("Escape")){
    Application.Quit();
   }
   
   // if the player is moving forwards...
   if(Input.GetAxis("Vertical") > .1 || Input.GetAxis("Vertical") < -.1 || Input.GetAxis("Horizontal") > .1 || Input.GetAxis("Horizontal") < -.1){
    
    // run or walk?
    if(Input.GetButton("Run"))
    {
     walkSpeed = 6.8;
     if(hasAnimation){ animation.CrossFade("run"); }
    } else {
     walkSpeed = 1.8;
     if(hasAnimation){ animation.CrossFade("walk"); }
    }
   
   }
   
   // if no movement, fade to idle
   else 
   {
    if(hasAnimation){ animation.CrossFade("idle"); }
   }
   
   /*if(Input.GetButton("Attack"))
      if(hasAnimation){ animation.Play("attack"); }
      else
      if(hasAnimation){ animation.CrossFade("idle"); }
   */
   ////////////////////////////////////////
   // prepare the players movement vector  //
   ////////////////////////////////////////
   
   // rotate the player based on horizontal movement requests
   var playerY = transform.eulerAngles.y;
   var cameraY = mainCamera.transform.eulerAngles.y;
   
   // default
   var playerRotY = cameraY;
   var playerMovX = 0;
   var playerMovZ = 0;
   
   // move north (relative to camera)
   if(Input.GetAxis("Vertical") > .1 && Input.GetAxis("Horizontal") > -.1 && Input.GetAxis("Horizontal") < .1){
    playerRotY = cameraY; // facing direction
    playerMovX = 0;
    playerMovZ = 1;
   }
   
   // move north east (relative to camera)
   if(Input.GetAxis("Vertical") > .1 && Input.GetAxis("Horizontal") > .1){
    playerRotY = cameraY + 45; // facing direction
    playerMovX = 0;
    playerMovZ = 1;
   }
   
   // move east (relative to camera)
   if(Input.GetAxis("Horizontal") > .1 && Input.GetAxis("Vertical") > -.1 && Input.GetAxis("Vertical") < .1){
    playerRotY = cameraY + 90; // facing direction
    playerMovX = 0;
    playerMovZ = 1;
   }
   
   // move south east (relative to camera)
   if(Input.GetAxis("Horizontal") > .1 && Input.GetAxis("Vertical") < -.1){
    playerRotY = cameraY + 135; // facing direction
    playerMovX = 0;
    playerMovZ = 1;
   }
   
   // move south (relative to camera)
   if(Input.GetAxis("Vertical") < -.1 && Input.GetAxis("Horizontal") > -.1 && Input.GetAxis("Horizontal") < .1){
    playerRotY = cameraY - 180; // facing direction
    playerMovX = 0;
    playerMovZ = 1;
   }
   
   // move south west (relative to camera)
   if(Input.GetAxis("Vertical") < -.1 && Input.GetAxis("Horizontal") < -.1){
    playerRotY = cameraY + 225; // facing direction
    playerMovX = 0;
    playerMovZ = 1;
   }
   
   // move west (relative to camera)
   if(Input.GetAxis("Horizontal") < -.1 && Input.GetAxis("Vertical") > -.1 && Input.GetAxis("Vertical") < .1){
    playerRotY = cameraY - 90; // facing direction
    playerMovX = 0;
    playerMovZ = 1;
   }
   
   // move north west (relative to camera)
   if(Input.GetAxis("Vertical") > .1 && Input.GetAxis("Horizontal") < -.1){
    playerRotY = cameraY - 45; // facing direction
    playerMovX = 0;
    playerMovZ = 1;
   }
   
   // if the character is moving, turn them to the direction they are moving in (relative to the camera)
   if(isMoving == true){
    var rotationDelay = Quaternion.Slerp(Quaternion.Euler(0, playerY, 0), Quaternion.Euler(0, playerRotY, 0), Time.deltaTime * 4);
    transform.rotation = rotationDelay;
   }
   
   // create a movement *unit* vector (relative to the players facing direction)
   moveDirection = Vector3(playerMovX,0,playerMovZ);
   
   // transform the direction vector from local space to world space
   moveDirection = transform.TransformDirection(moveDirection);
   
   // check if the character has been set into motion
   if(moveDirection == Vector3.zero){
    isMoving = false;
   } else {
    isMoving = true;
   }
  }
  
  /////////////////////////
  // transform the player  //
  /////////////////////////
  
  // push the player down with gravity (this is blocked by terrain collision though)
  moveDirection.y -= gravity * Time.deltaTime;
  
  // transform the character with the movement vector
  charController.Move(moveDirection * (Time.deltaTime * walkSpeed));
 }
 
 ////////////////////////////////////////////////////////////////////////////
 // FUNCTION :: ClampAngle ////////////////////////////////////////////////
 ////////////////////////////////////////////////////////////////////////////
 
 static function ClampAngle (angle : float, min : float, max : float)
 {
     if (angle < -360)
     {
         angle += 360;
     }
  if (angle > 360)
  {
         angle -= 360;
     }
 
     return Mathf.Clamp (angle, min, max);
 }