Problem with referencing gameobjects in a if statement

I'm following a tutorial that's in javascript and I'm converting the code over to C# and I'm running into a problem at the end of the tutorial. The problem I'm having is running into this line of code:

for(theMuzzlePos in muzzlePositions) { Instantiate(myProjectile, theMuzzlePos.position, theMuzzlePos.rotation); Instantiate(muzzleEffect, theMuzzlePos.position, theMuzzlePos.rotation); }

C# apparently does not recognize "in" in the conditional statement. What can I do to change this and reference those gameobjects?

 using UnityEngine;
 using System.Collections;
 
 public class Turret_Script : MonoBehaviour {
     
     public GameObject myProjectile;
     public float reloadTime = 1f;
     public float turnSpeed = 5f;
     public float firePauseTime =.25f;
     public GameObject muzzleEffect;
     public float errorAmount = .001f;
     public Transform myTarget;
     public Transform[] muzzlePositions;
     public Transform turretBall;
     
     private float nextFireTime;
     private float nextMoveTime;
     private Quaternion desiredRotation;
     private float aimError;
 
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
         if(myTarget)
         {
             if(Time.time >= nextMoveTime)
             {
                 CalculateAimPosition(myTarget.position);
                 turretBall.rotation = Quaternion.Lerp(turretBall.rotation, desiredRotation, Time.deltaTime*turnSpeed);
             }
             if(Time.time >= nextFireTime)
             {
                 FireProjectile();
             }
         }
     }
     
     void OnTriggerEnter(Collider other )
     {
         if(other.gameObject.tag == "Enemy")
         {
             nextFireTime = Time.time +(reloadTime*.5);
             myTarget = other.gameObject.transform;
         }
     }
     
     void OnTriggerExit(Collider other)
     {
         if(other.gameObject.transform == myTarget)
         {
             myTarget = null;
         }
     }
     
     void CalculateAimPosition(Vector3 targetPos)
     {
         var aimPoint = new Vector3(targetPos.x+aimError, targetPos.y+aimError, targetPos.z+aimError);
         desiredRotation = Quaternion.LookRotation(aimPoint);
     }
     
     void CalculateAimError()
     {
         aimError = Random.Range (-errorAmount, errorAmount);
     }
     
     void FireProjectile()
     {
         audio.Play();
         nextFireTime = Time.time+reloadTime;
         nextMoveTime = Time.time+firePauseTime;
         CalculateAimError();
         
         for(theMuzzlePos in muzzlePositions)
         {
             Instantiate(myProjectile, theMuzzlePos.position, theMuzzlePos.rotation);
             Instantiate(muzzleEffect, theMuzzlePos.position, theMuzzlePos.rotation);
         }
     }
 }