> <@diondokter:matrix.org> This looks promising: https://docs.rs/stack_dst/latest/stack_dst/value/struct.Value.html

 * Ah yes, this works!
Never saw this crate before. It was started 9 years ago!

They give this example:
```rust
use stack_dst::Value;

// The closure is stored in two 64-bit integers (one for the vtable, the other for the value)
fn make_closure(value: u64) -> Value<dyn Fn()->String, ::stack_dst::buffers::U64_2> {
    if value < 0x10000 {
        ValueA::new_stable(move || format!("Hello there! value={}", value), |v| v as _).ok().expect("Closure doesn't fit")
    }
    else {
        ValueA::new_stable(move || format!("Hello there! value={:#x}", value), |v| v as _).ok().expect("Closure doesn't fit")
    }
}
let closure = make_closure(12);
assert_eq!( closure(), "Hello there! value=12" );
```