What's the scope in object literal definitions.

Question

I am learning javascript and my current understanding is the main way javascript uses for scoping is the function scope, and there are no block scopes in general.

So I came up with this:

var obj = {
  foo: function myfunc() {
    console.log("123");
  }
};

myfunc();

I thought because javascript doesn't have block scoping, the definition of myfunc() will be visible in global scope. But it actually did not. Can someone help to explain this?

It's a function expression. It never becomes available in any scope. — Bergi, Jun 17 '16 at 15:49
@Bergi Yes, but my question is does literal object definitions create a block scope — shengy, Jun 17 '16 at 15:50
@dangor I know I can't, cause I tried it, but is there any place documents this? does the object creation define a block scope? — shengy, Jun 17 '16 at 15:52
Also `var foo = function myfunc() {}; myfunc();` does not work, because of the expression. — t.niese, Jun 17 '16 at 15:52

score 2 · Accepted Answer · edited May 23 '17 at 12:08

2

There are three points where your understanding is flawed:

JavaScript does have block scopes since ES6.
Object literals are no blocks, they do not introduce any scopes.
Your function is not becoming a global because it is not a declaration (which is syntactically invalid inside an object), but a function expression that just creates a named function object which then is assigned to the foo property of the newly created object. See var functionName = function() {} vs function functionName() {} for details.

edited May 23 '17 at 12:08

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answered Jun 17 '16 at 15:56

Bergi

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@shengy: The downvote means "*This question does not show any research effort; it is unclear or not useful*". – Bergi Jun 17 '16 at 16:02

What's the scope in object literal definitions.

1 Answers1