unity3d – How do I fix an Invalid Expression Term ‘=’ error in Unity/C#?

Heyo, not very familiar with C#, much less Unity, and I’m apparently doing something wrong, here’s my code, THe only error I get is:

‘Invalid Expression Term “=”‘

    bool currentlydown;
// further up the script
void Start() {
        currentlydown = false;
    }
// later up the script
void Update() {
if ((Input.GetKeyDown("W") || Input.GetKeyDown("A") || Input.GetKeyDown("S") || Input.GetKeyDown("D")) && currentlydown === false) {
            anim.SetBool("Walking", true);
            currentlydown = true;
        } else if (!(Input.GetKeyDown("W") || Input.GetKeyDown("A") || Input.GetKeyDown("S") || Input.GetKeyDown("D")) && currentlydown === true){
            anim.SetBool("Walking", false);
            currentlydown = false;
        }
    }

Any and all help is appreciated!