Struct ExceptionValue 

pub struct ExceptionValue {
    pub type_name: String,
    pub message: String,
    pub cause: Option<Box<Self>>,
    pub args: Vec<Value>,
    pub stamped_line: Option<u32>,
    pub exceptions: Option<Vec<Self>>,
}

A runtime exception value that can be raised and caught by user code.

args holds the positional constructor arguments (CPython’s e.args). For exceptions constructed via the user-facing constructor (ValueError('msg')), this is populated from the call args; for internally-raised exceptions (KeyError on dict miss, IndexError on out-of-range subscript) it defaults to empty and exception_attribute.args synthesizes (message,) to match CPython’s auto-arg behaviour.

stamped_line is set by stamp_line at the eval_stmt boundary and rendered ONLY at the Interpreter::execute boundary into the user-facing errorMessage — it is deliberately invisible to str(e) / repr(e) / print(f'{e}') inside the script, so the agent-loop debug suffix doesn’t bleed into user code that catches and inspects exceptions.

Constructed via ExceptionValue::new + the with_* chain — the struct fields are public for the rare consumer that wants to pattern-destructure, but new construction sites should not use struct-literal form.

Fields

type_name: String

message: String

cause: Option<Box<Self>>

args: Vec<Value>

stamped_line: Option<u32>

exceptions: Option<Vec<Self>>

Nested exceptions for ExceptionGroup / BaseExceptionGroup (PEP 654).

Implementations

impl ExceptionValue

pub fn new(type_name: impl Into<String>, message: impl Into<String>) -> Self

Build the standard <Type>: <message> exception with no cause, no line stamp. The 95% case.

args mirrors CPython’s positional-args behaviour: an empty message yields args == () (matching Exception()), and a non-empty message yields args == (message,) (matching Exception('msg')). Multi-arg constructors and internal raisers that need a non-message arg layout call Self::with_args to override.

pub fn group( type_name: impl Into<String>, message: impl Into<String>, exceptions: Vec<Self>, ) -> Self

Build an ExceptionGroup (or BaseExceptionGroup) with nested exceptions.

pub fn with_cause(self, cause: Self) -> Self

Attach a raise X from Y-style cause.

pub fn with_args(self, args: Vec<Value>) -> Self

Set the constructor args. Used at the call-as-constructor path (ValueError('msg', 'detail')) so e.args reflects the exact values the user passed.

pub fn key_error(key: impl Display) -> Self

KeyError(<key>) — used by every dict/Counter/defaultdict miss. CPython’s KeyError message is the key’s repr.

pub fn index_error(kind: &str) -> Self

IndexError(<kind> index out of range) — CPython varies the wording by container; pass the type-specific kind (list, tuple, string, bytes, range object, deque).

pub fn zero_division_error(message: impl Into<String>) -> Self

ZeroDivisionError(division by zero) — CPython’s canonical wording for 1/0.

Trait Implementations

impl Clone for ExceptionValue

fn clone(&self) -> ExceptionValue

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ExceptionValue

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

Formats the value using the given formatter.

impl Default for ExceptionValue

fn default() -> ExceptionValue

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ExceptionValue

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for ExceptionValue

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.