add
Adds all arguments passed, except those already present.
Throws a "SyntaxError" DOMException if one of the arguments is the empty string.
Throws an "InvalidCharacterError" DOMException if one of the arguments contains any ASCII whitespace.
Adds all arguments passed, except those already present.
Throws a "SyntaxError" DOMException if one of the arguments is the empty string.
Throws an "InvalidCharacterError" DOMException if one of the arguments contains any ASCII whitespace.