public String toString() {
    String s = "Function:\n  Name: "+name+"\n  args: ";
    for(String a:argnames) {
      s+=a+" ";
    }
    s+="\n  rets: ";
    for(String r:returnnames) {
      s+=r+" ";
    }
    s+="\n  Code:\n";
    for(String c:code) {
      s+="    "+c+"\n";
    }
    return s;
  }