MENU

Scoping and Hoisting

Assuming Strict Mode(II) and anonymous functions are not used, scope-wise, a function declaration is identical to a 'var' variable declaration.

Functions declared within a local block are accessible outside the parent function but hoisted within the block only.

// f();  // TypeError

{
  f();
  function f() {
    console.log('hi');
  }
}

f();

// f();  // TypeError

{
  f();
  function f() {
    console.log('hi');
  }
}

f();

Functions declared within another function are accessible and hoisted within the parent function only.

function f() {
  g();
  function g() {
    console.log('hi');
  }
}

f();
g();

function f() {
  g();
  function g() {
    console.log('hi');
  }
}

f();
g();