Without them crashing the app running them?  Say by wrapping with try / catch?

You can assume that I've limited the opcode addresses to the program and/or the data section which I'll try to put right next to the code.

Reason is so I don't have to make my own VM.

I want to mutate computable functions in a genetic-algorithm style, so in order to include the full space of computable functions I need a full programming language, or a VM that includes conditional jump instructions.

The purpose of it is to make a real-time, short-lived function predictor.

On Tuesday, 18 July 2017 at 17:35:17 UTC, Enjoys Math wrote:
> Without them crashing the app running them?  Say by wrapping with try / catch?

Run them in a separate process, so it can die independently.

On Tuesday, 18 July 2017 at 17:35:17 UTC, Enjoys Math wrote:
> Without them crashing the app running them?  Say by wrapping with try / catch?

and, most probably a timeout, as  you're certainly going to run into infinite loops.

> Reason is so I don't have to make my own VM.

Why not reuse an existing one? Some of them are very simple:
https://github.com/munificent/wren

It will be a lot easier than trying to generate random *compilable* D programs ; and will avoid requiring a compilation step in your mutation loop (I know the D compiler is fast, but still :-) ).

On Tuesday, 18 July 2017 at 17:35:17 UTC, Enjoys Math wrote:
>
> The purpose of it is to make a real-time, short-lived function predictor.

I'm genuinely curious. What is a function predictor used for?