http://www.ecma-international.org/ecma-262/5.1/#sec-4.3.19 http://www.ecma-international.org/ecma-262/5.1/#sec-4.3.19 As for why? I have no clue. It's specifie

http://www.ecma-international.org/ecma-262/5.1/#sec-4.3.19 http://www.ecma-international.org/ecma-262/5.1/#sec-4.3.19 As for why? I have no clue. It's specified in the specification. That's all. There are ToInteger(), ToInt32(), ToUint16(), ToUInt32 functions defined as well, but I think that's for the host to implement EDIT: oops. there isn't a ToInt64() function defined.