Javascript：函数和数组作为键/值对

Question

1) In some other languages define function as parameterized block of statements, and on syntactic level javascript function also looks like this, until it's said that it can have it's own properties and methods.How can it be syntactically represented as key/value pair? And where does function code live?

 var x = function(a,b){alert('Hi');};
    // x = { _code: "alert('Hi'), _arguments: {a:.., b:..,}}

here code and arguments are my imaginary internal properties

2) If array is key/value pair, can i think that array indexes are just object keys?

var a = ["elem1", "elem2"];
// a = {0: "elem1", 1: "elem2"}

Answer 1

Expanding on my comment that EVERYTHING in JavaScript is a object.

var arr = [

  function () {

    console.log("Well... Look at that.");

  }

];


var obj = arr[0];

obj();

var newObj = Object.assign({}, arr);

console.log(newObj);

newObj[0]();

Answer 2

How can it be syntactically represented as key/value pair?

It can't.

The executable code of a function is not expressed in terms of properties on an object.

And where does function code live?

That's an implementation detail of the JavaScript engine, not something that is exposed to JavaScript code in a standard way.

If array is key/value pair, can i think that array indexes are just object keys?

They are just properties. See the specification :

Array objects give special treatment to a certain class of property names. A property name P (in the form of a String value) is an array index if and only if ToString(ToUint32(P)) is equal to P and ToUint32(P) is not equal to 2 ³² −1. A property whose property name is an array index is also called an element. Every Array object has a length property whose value is always a nonnegative integer less than 2 ³² . The value of the length property is numerically greater than the name of every property whose name is an array index;

… and so on.