Category: computers

Well, i did the equivalent thing in the C++ world. Back in 1986 and 1987 I worked in the C++ group at Bell Labs. I was trying to debug my program, but could not understand what I was seeing from the linker–mangled symbol names generated by cfront. The documentation I was reading said I could use the demangler to figure out what the output meant, but I could not find it. In frustration I sent out an email to the group and got a message back from Bjarne Stroustrup saying something like, “It hasn’t been written yet, would you like to write it?”

The program I created was called c++filt. The way it worked was to read standard input and try to demangle every c identifier it found. This meant we could fix the output from the linker without actually hacking it in any way. It seems that there is still a program floating around called c++filt and it works mostly the same way. I was never able to prove that I did this until recently, when a co-worker, Bryce Leblach, found a reference to me on page 197 of the AT&T documentation from cfront. Okay, so I didn’t invent C++ or any important language feature, but I did make a tiny contribution to the history of the language, one little glittering sequin on the dazzling C++ coat.

Java is a great language, but it’s missing a feature present in its cousin languages, C++ and C. The feature is the builtin macros __FILE__ and __LINE__. These are often quite useful for debugging, etc. Well, even though Java doesn’t have them as builins, you can still make your own.

public class MacroHack {
   public static String __FILE__() {
      return new Throwable().getStackTrace()[1].getFileName();
   }
   public static int __LINE__() {
      return new Throwable().getStackTrace()[1].getLineNumber();
   }
}

Since we lost the controller for our Roku, I’ve had a bit of fun after discovering that you could control it by telnetting to port 8080 on the device and sending it commands such as “press up”, “press right”, etc. To make this easier, I created a small application which you can access here.