1 Error is a function 2 EvalError is a function 3 RangeError is a function 4 ReferenceError is a function 5 SyntaxError is a function 6 TypeError is a function 7 URIError is a function 8 Error.arity 1 9 EvalError.arity 1 10 RangeError.arity 1 11 ReferenceError.arity 1 12 SyntaxError.arity 1 13 TypeError.arity 1 14 URIError.arity 1 15 true 16 my error 17 Error 18 thrown @ 49 19 true 20 ReferenceError 21 "foo" is not defined 22 true 23 TypeError 24 Object.foo_method is not a function 25 Error 26 EvalError 27 RangeError 28 ReferenceError 29 SyntaxError 30 TypeError 31 URIError