What is the difference between new Foo and new Foo() in javascript?

Question

I know the difference between two in C++, but don't know if it's the same for JS also

Answer 1

From my experience there is no difference other then with new Foo you can't pass any parameters and with new Foo() you can.

Answer 2

From the ECMAScript Language Specification for new:

new NewExpression:

Call the [[Construct]] method on Result(2), providing no arguments

new MemberExpression Arguments

Call the [[Construct]] method on Result(2), providing the list Result(3) as the argument values.

It's simply a matter of whether the constructor receives any arguments or not.