Enum VmError 

pub enum VmError {
    DialogueNotStarted,
    DialogueNotFinished,
    DialogueAlreadyFinished,
    DialogueNodeNotFound(NodeName),
    ChoiceOutOfRange {
        index: usize,
        count: usize,
    },
    WrongResumeEvent,
    StepLimitExceeded,
    ExprEvalError(EvalError),
    NoAvailableChoice,
    ChoiceNotAvailable(usize),
}

Everything that can go wrong while running a Dialogue.

A failed call never changes the state of the VM. After an error it is still suspended exactly where it was, and the host can resume with a valid answer.

Variants

DialogueNotStarted

DialogueVm::resume was called before DialogueVm::start.

DialogueNotFinished

DialogueVm::start was called while a dialogue is still running. Starting again is only allowed once the current one is finished.

DialogueAlreadyFinished

DialogueVm::resume was called after DialogueEvent::Finished.

DialogueNodeNotFound(NodeName)

A node was asked for by name, by DialogueVm::start and the Dialogue has none.

ChoiceOutOfRange

ResumeEvent::Select carried an index no choice has.

Fields

index: usize

count: usize

WrongResumeEvent

The ResumeEvent does not fit the DialogueEvent the VM emitted, such as an Advance on a pending choice.

StepLimitExceeded

Too many steps were walked without anything to hand back to the host, which means the dialogue loops on itself.

ExprEvalError(EvalError)

Error when evaluating expression

NoAvailableChoice

No choice are available

ChoiceNotAvailable(usize)

The selected choice was not available

Trait Implementations

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.