JS: Creating a Promise class — how does function take an arg?

I am looking at an implementation of a Promise class (at bottom). The constructor takes a function, f.
So if I have a regular function I want to pass in:

function myFunc() {
    console.log("My Func");

If a Promise looks like this :

let promise = new Promise(resolve => {

then I am confused as to what f represents now though in the constructor of the class below. It appears as though resolve is the argument, not a function, f.

*Promise Class

class Promise {
    constructor(f) {
         this.onResolves = [];
         this.status = "pending";
         const resolve = value => {
           this.status = "resolved";
           this.value = value;
    callOnResolves() {
         if (this.status === "resolved") {
           this.onResolves.forEach(onResolve => onResolve(this.value));
           this.onResolves.length = 0;
    then(onResolve) {
         return new Promise(resolve => {
           this.onResolves.push(value => resolve(onResolve(value)));

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