Array like syntax support

[krichprollsch]

Many DOM objects like HTMLCollection [1] supports array like usage with square brackets

Example from MDN

let elem1, elem2;

// document.forms is an HTMLCollection

elem1 = document.forms[0];
elem2 = document.forms.item(0);

alert(elem1 === elem2); // shows: "true"

elem1 = document.forms.myForm;
elem2 = document.forms.namedItem("myForm");

alert(elem1 === elem2); // shows: "true"

elem1 = document.forms["named.item.with.periods"];

jsruntime-lib should allow to implement the array like syntax (getter and setter) with a native struct.