javascript - difference between numbers using or without using variable

Question

What's the difference between the following code?

var a = 1;
a.toString(); // outputs: "1"

But this throws an error:

1.toString();

SyntaxError: Unexpected token ILLEGAL

Why? Why does the first code work but the second code throws an error?

Answer 1

With method invocations, it is important to distinguish between the floating-point dot and the method invocation dot. Thus, you cannot write 1.toString(); you must use one of the following alternatives:

1..toString()
1 .toString() //space before dot
(1).toString()
1.0.toString()