Struct ConstrainedDecoder 

pub struct ConstrainedDecoder { /* private fields */ }

High-level orchestrator for constrained LLM decoding.

This struct manages the decode loop for generating TØR-G graphs from an LLM. It maintains builder state, generates masks, and converts LLM tokens back to TØR-G tokens.

Example

let mapping = TokenMapping::sequential(256);
let generator = MaskGenerator::new(mapping, vocab_size);
let mut decoder = ConstrainedDecoder::new(generator);

while !decoder.is_complete() {
    let mask = decoder.next_mask();
    mask.apply_to_logits(&mut logits);
    let token_id = sample(&logits);
    decoder.feed_token(token_id)?;
}

let graph = decoder.finish()?;

Implementations

impl ConstrainedDecoder

pub fn new(generator: MaskGenerator) -> Self

Create a new constrained decoder with default limits.

pub fn with_limits(generator: MaskGenerator, limits: Limits) -> Self

Create a new constrained decoder with custom limits.

pub fn phase(&self) -> Phase

Get the current build phase.

pub fn is_complete(&self) -> bool

Check if decoding is complete.

Returns true when the graph is in a completable state (at least one output declared) or when the builder is in the Done phase.

pub fn next_mask(&self) -> LogitMask

Generate the logit mask for the next token.

Apply this mask to your LLM’s logits before sampling.

pub fn feed_token(&mut self, llm_token_id: u32) -> Result<(), DecodeError>

Feed an LLM token ID into the decoder.

The token ID is reverse-mapped to a TØR-G token and pushed to the internal builder.

Errors

Returns an error if:

• The token ID doesn’t map to a valid TØR-G token
• The token is not valid in the current builder state

pub fn finish(self) -> Result<Graph, BuildError>

Finish decoding and return the constructed graph.

Errors

Returns an error if the graph is incomplete (e.g., no outputs declared).

pub fn builder(&self) -> &Builder

Get a reference to the internal builder.

pub fn generator(&self) -> &MaskGenerator

Get the mask generator.

Trait Implementations

impl Debug for ConstrainedDecoder

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

Formats the value using the given formatter.