fun/README_DEV.md

Developer Notes

This project splits VM opcode handlers into one-include-per-op file for readability. The main interpreter loop (src/vm.c, vm_run) includes vm_case_*.inc files, each containing a single case OP_*: { ... } handler.

Adding a new opcode

1. Add the enum in src/bytecode.h (e.g., OP_FOO) and add its human-readable name to opcode_names[] in src/vm.h. Update opcode_is_valid upper bound if needed.
2. Implement the VM handler in src/vm_case_foo.inc using the established style:
   • No function wrappers, just case OP_FOO: { ... break; }.
3. Include the new file in the switch inside src/vm.c (vm_run), near similar ops.
4. Run the checker script: