FunctionsCannotBeImmediatelyInvoked

DRAFT

Observed

Correction

Here is what's right.

There are two ways to define a function:

• through a function declaration:

  function foo() {} // function declaration
  () => {}; // arrow function declaration

• through a function expression:

  // function expressions
  (function foo() {});
  const foo = function () {};
  const bar = { foo: function () {} }(
    // arrow function expressions
    () => {}
  );
  const foo = () => {};
  const bar = { foo: () => {} };

Function declarations cannot be immidiately invoked:

Function expressions can be invoked as they are defined:

Difficult cases

Internal scope

Function expressions can be named, meaning that it is possible to access the function from within its own scope:

Function expressions are not function declarations

A function expression does not declare the function in the containing scope of the expression.