sequenceDiagram
    participant Parser as AST Parser
    participant Comp as CompileError / ParseError
    participant VM as VM Exception Layer
    participant PyErr as Python SyntaxError Obj

    rect rgb(230,245,230)
    Note over Parser,Comp: Parse-time error detection
    Parser->>Comp: produce parse error with start/end range
    Comp->>Comp: compute start_location and end_location
    Comp->>VM: return/raise ParseError (includes end_location)
    end

    rect rgb(230,230,245)
    Note over VM,PyErr: VM constructs Python SyntaxError
    VM->>VM: set lineno and offset from error.location
    VM->>VM: call error.python_end_location()
    alt end location present
        VM->>PyErr: set end_lineno and end_offset
    else no end location
        VM->>PyErr: leave end attributes unset
    end
    end

    rect rgb(245,240,230)
    Note over VM,PyErr: Exception rendering (display)
    VM->>VM: compare lineno and end_lineno
    alt same_line == true
        VM->>VM: compute caret range using offset..end_offset
        VM->>PyErr: render caret under same line
    else same_line == false
        VM->>PyErr: render single-point marker (no caret)
    end
    end