super(name, parameters, required);
this.fun = fun;
}
@Override public RNode create(ASTNode call, RSymbol[] names, RNode[] exprs) {
final ArgumentInfo ai = check(call, names, exprs);
return new Builtin(call, names, exprs) {
@Override public RAny doBuiltIn(Frame frame, RAny[] args) {
RAny res = fun.invoke(ai, args);
return res;
}