Struct StackFrame 

pub struct StackFrame {
    pub filename: String,
    pub start: CodeLoc,
    pub end: CodeLoc,
    pub frame_name: Option<String>,
    pub preview_line: Option<Arc<str>>,
    pub hide_caret: bool,
    pub hide_frame_name: bool,
}

A single frame in a Python traceback.

Contains all the information needed to display a traceback line: the file location, function name, and optional source code preview.

Caret Markers

Monty uses only ~ characters for caret markers in tracebacks, unlike CPython 3.11+ which uses ~ for the function name and ^ for arguments (e.g., ~~~~~~~~~~~^^^^^^^^^^^). This simplification is intentional - Monty marks the entire expression span uniformly.

Fields

filename: String

The filename where the code is located.

start: CodeLoc

Start position in the source code.

end: CodeLoc

End position in the source code.

frame_name: Option<String>

The name of the frame (function name, or None for module-level code).

preview_line: Option<Arc<str>>

The source code line for preview in the traceback.

Stored as Arc<str> rather than String so that consecutive frames referencing the same source line — typical of recursion and tight helper-function loops — share a single allocation. Without sharing, a 1000-deep recursive call into code on a long line would clone the entire line into each frame and amplify memory usage by the call depth. Serialization roundtrips lose the sharing (each frame gets its own Arc), but that is bounded by the wire size of the traceback so does not regress the amplification.

hide_caret: bool

Whether to hide the caret marker in the traceback for this frame.

Set to true for:

• raise statements (CPython doesn’t show carets for raise)
• AttributeError on attribute access (CPython doesn’t show carets for these)

hide_frame_name: bool

Whether to hide the , in <name> part of the frame line.

Set to true for SyntaxError where CPython doesn’t show the frame name. CPython’s SyntaxError format: File "...", line N vs runtime error format: File "...", line N, in <module>

Trait Implementations

impl Clone for StackFrame

fn clone(&self) -> StackFrame

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for StackFrame

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for StackFrame

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for StackFrame

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

Formats the value using the given formatter.

impl PartialEq for StackFrame

fn eq(&self, other: &StackFrame) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for StackFrame

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for StackFrame