monty_types/
results.rs

1//! Host-supplied results fed back into a suspended run:
2//! [`NameLookupResult`] and [`ExtFunctionResult`].
3
4use crate::{exceptions::MontyException, object::MontyObject};
5/// Result of a name lookup from the host.
6///
7/// When the VM encounters an unresolved name, the host provides one of these:
8/// - `Value(obj)`: The name resolves to this value (cached in the namespace for future access).
9/// - `Undefined`: The name is truly undefined, causing `NameError`.
10#[derive(Debug)]
11pub enum NameLookupResult {
12    /// The name resolves to this value.
13    Value(MontyObject),
14    /// The name is undefined — VM will raise `NameError`.
15    Undefined,
16}
17
18impl From<MontyObject> for NameLookupResult {
19    fn from(value: MontyObject) -> Self {
20        Self::Value(value)
21    }
22}
23
24/// Return value or exception from an external function.
25#[derive(Debug)]
26pub enum ExtFunctionResult {
27    /// Continues execution with the return value from the external function.
28    Return(MontyObject),
29    /// Continues execution with the exception raised by the external function.
30    Error(MontyException),
31    /// Pending future — the external function is a coroutine.
32    ///
33    /// The `u32` is the `call_id` from the `FunctionCall` that created this
34    /// snapshot. It is used to track the pending future so it can be resolved
35    /// later via `ResolveFutures::resume()`.
36    Future(u32),
37    /// The function was not found, should result in a `NameError` exception.
38    NotFound(String),
39}
40impl From<MontyObject> for ExtFunctionResult {
41    fn from(value: MontyObject) -> Self {
42        Self::Return(value)
43    }
44}
45
46impl From<MontyException> for ExtFunctionResult {
47    fn from(exception: MontyException) -> Self {
48        Self::Error(exception)
49    }
50}
monty_types/results.rs

monty_types/
results.rs
