Disclaimer This project is a joke and should be taken seriously only by people without humor.

This project provides the ppx_useless OCaml compiler extension, that replaces the code with the following statement:

let () = ()

Now this might seem controversial to the casual, but there are benefits to be had.

Useless features:

• Reduces compile errors
• Reduces runtime errors
• Reduces binary size
• Simplifies debugging
• Increases speed
• Decreases memory usage (both at compile-time and run-time)

Useful features:

• Wastes CPU cycles, which in turn heats your room
• There's at least a possibility that the program produces the desired output, which means that any input would suffice as a solution, which in turn saves time for the programmer.

However, some programs are not expected to terminate (e.g. server programs) and for those kinds of programs the ppx_diverge is provided that replaces every expression with:

let rec diverge () = diverge () in diverge ()

which provides the desired non-termination. An added benefit here is that there's no longer any need for messing about with configuration files!

Here the observant reader interjects: "But even a trivial but deterministic program can be useful (e.g. /bin/true)!" True, true is a very useful program and to address that the ppx_nondeterministic extension is provided. Here's a sample session from utop:

> 2+2;;
- : int = 4

> 2+2;;
- : int = 3

> 2+2;;
- : int = 5

Observe here that there is a possibility of obtaining the expected result. And be honest, who doesn't what more non-determinism in their lives?

The provided Makefile contains instructions on how to build the different useless extensions, but the impatient can invoke utop like so:

• for useless programs: make useless-utop
• for non-terminating programs: make diverge-utop
• for non-deterministic programs: make nondeterministic-utop