tidepool_codegen/
yield_type.rs

1/// Result of a single evaluation step.
2#[derive(Debug, PartialEq, Eq)]
3pub enum Yield {
4    /// Pure result — evaluation complete.
5    Done(*mut u8),
6    /// Effect request — stash continuation, dispatch to handler.
7    /// Fields: (union_tag: u64, request: *mut u8, continuation: *mut u8)
8    Request {
9        tag: u64,
10        request: *mut u8,
11        continuation: *mut u8,
12    },
13    /// Evaluation error.
14    Error(YieldError),
15}
16
17impl std::fmt::Display for Yield {
18    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
19        match self {
20            Yield::Done(ptr) => write!(f, "Done({:p})", ptr),
21            Yield::Request {
22                tag,
23                request,
24                continuation,
25            } => {
26                write!(
27                    f,
28                    "Request(tag={}, req={:p}, cont={:p})",
29                    tag, request, continuation
30                )
31            }
32            Yield::Error(e) => write!(f, "Error({})", e),
33        }
34    }
35}
36
37#[derive(Debug, PartialEq, Eq, Clone, Copy)]
38pub enum YieldError {
39    /// Result HeapObject had unexpected tag byte.
40    UnexpectedTag(u8),
41    /// Result was Con but con_tag was neither Val nor E.
42    UnexpectedConTag(u64),
43    /// Val constructor had wrong number of fields.
44    BadValFields(u16),
45    /// E constructor had wrong number of fields.
46    BadEFields(u16),
47    /// Union constructor had wrong number of fields.
48    BadUnionFields(u16),
49    /// Null pointer encountered.
50    NullPointer,
51    /// Division by zero in JIT code.
52    DivisionByZero,
53    /// Arithmetic overflow in JIT code.
54    Overflow,
55}
56
57impl std::fmt::Display for YieldError {
58    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
59        match self {
60            YieldError::UnexpectedTag(tag) => write!(f, "unexpected heap tag: {}", tag),
61            YieldError::UnexpectedConTag(tag) => write!(f, "unexpected constructor tag: {}", tag),
62            YieldError::BadValFields(n) => {
63                write!(f, "Val constructor has {} fields, expected >= 1", n)
64            }
65            YieldError::BadEFields(n) => write!(f, "E constructor has {} fields, expected 2", n),
66            YieldError::BadUnionFields(n) => {
67                write!(f, "Union constructor has {} fields, expected 2", n)
68            }
69            YieldError::NullPointer => write!(f, "null pointer in effect result"),
70            YieldError::DivisionByZero => write!(f, "division by zero"),
71            YieldError::Overflow => write!(f, "arithmetic overflow"),
72        }
73    }
74}
75
76impl std::error::Error for YieldError {}
tidepool_codegen/yield_type.rs

tidepool_codegen/
yield_type.rs
