Enum ConstraintError 

pub enum ConstraintError {
    VocabMismatch {
        got: usize,
        expected: usize,
    },
    NoAllowedToken {
        accepted: usize,
    },
    TokenOutOfVocab {
        token: usize,
        vocab_size: usize,
    },
    Grammar(GrammarError),
}

A constrained-sampling failure. Kept separate from GrammarError, which is about a grammar, because every variant here is about the grammar’s fit to a vocabulary or to a caller’s logits.

Variants

VocabMismatch

The logits handed to the mask are not vocabulary-shaped.

The live cause is a backend that folded lm_head + argmax onto the device and returned a one-element vector holding a token id (ferrox_server::generate::greedy_gpu_fold_allowed). Masking that would zero a token id rather than a logit, so it is refused rather than performed on the wrong thing.

Fields

got: usize

expected: usize

NoAllowedToken

The grammar forbids every token in the vocabulary, and the parse is NOT complete.

Not a bug in the grammar engine: it is a grammar this vocabulary cannot spell (a rule requiring a character no token piece contains), and the only alternative to refusing is to sample from an all--inf distribution, i.e. to emit an arbitrary token and call it constrained output.

The complete case is MaskOutcome::Complete and is not an error: nothing left to say, having said everything, is an answer.

Fields

accepted: usize

TokenOutOfVocab

A token id outside the snapshotted vocabulary was accepted.

Fields

token: usize

vocab_size: usize

Grammar(GrammarError)

The grammar itself refused.

Trait Implementations

impl Debug for ConstraintError

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

Formats the value using the given formatter.

impl Display for ConstraintError

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

Formats the value using the given formatter.

impl Error for ConstraintError

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.

impl From<GrammarError> for ConstraintError

fn from(source: GrammarError) -> Self

Converts to this type from the input type.