Enum VmError 

pub enum VmError {
    Panic(String),
    TypeMismatch(String),
    StackUnderflow,
    UnknownFunction(String),
    Effect(String),
    ProcessExit(i32),
    CallStackOverflow(u32),
    RefinementFailed {
        fn_name: String,
        param_index: usize,
        binding: String,
        reason: String,
    },
    DivByZero {
        op: &'static str,
    },
}

Variants

Panic(String)

TypeMismatch(String)

StackUnderflow

UnknownFunction(String)

Effect(String)

ProcessExit(i32)

The program called std.process.exit(code) (#754).

Not a failure — a deliberate signal — but it travels the error channel because that is the VM’s only unwind path, and unwinding is the point: the alternative is calling std::process::exit inside the handler, which would terminate the process where it stands and silently skip everything lex run does after the call returns (finalising the trace, writing the Trace attestation, recording committed ops). A run that exits is still a run that happened, and it should leave the same evidence.

CallStackOverflow(u32)

RefinementFailed

Refinement predicate failed at a call boundary (#209 slice 3). Surfaced when a function declares param :: Type{x | predicate}, the call-site arg couldn’t be discharged statically (slice 2), and the runtime evaluator finds the predicate is false for the actual argument value. The verdict mirrors the shape of gate.verdict-style records in lex-trace.

Fields

fn_name: String

param_index: usize

binding: String

reason: String

DivByZero

Integer division or modulo with a zero divisor (#696). Without this guard the host //% panics and takes the whole process down — the crash report had a conformance harness compute a rate over an empty set in teardown, far from any user-visible division. Surfacing a catchable VmError instead keeps the failure inside the language’s error model. Float div/mod is exempt: IEEE-754 yields inf/NaN rather than trapping.

Fields

op: &'static str

"division" or "modulo" — names the offending operator.

Trait Implementations

impl Clone for VmError

fn clone(&self) -> VmError

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for VmError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for VmError

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for VmError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.