class

DCCD

local dc = Grammar.dccd(ctx, vocab, {
    seq_id            = session.seq_id,
    draft_sampler     = free_sampler,
    constrain_sampler = grammar_sampler,
    max_draft_tokens  = 128,
    close_thinking    = true,   -- required for Qwen3.5 / DeepSeek-R1
})
local result = dc:generate()
print(result.text)   -- grammar-valid output
print(result.draft)  -- unconstrained draft for debugging

Functions

DCCD.new DCCD:_run_pass DCCD:generate DCCD:best_of

DCCD.new

Create a DCCD generator.

DCCD.new(ctx, vocab, opts)

ctxanyion7-core Context.

vocabanyion7-core Vocab.

optstable

→ DCCD

DCCD:_run_pass

DCCD:_run_pass(sampler, max_tokens, on_token)

DCCD:generate

Generate using Draft-Conditioned Constrained Decoding. Implements the algorithm from arXiv:2603.03305 (Feb 2026). Requires the configured seq to already hold the prompt — call after your pipeline has decoded the prompt tokens into that seq.

DCCD:generate(opts)

optstable?

→ table?

DCCD:best_of

Convenience: run DCCD with best-of-K draft selection.

DCCD:best_of(k, opts)

knumberNumber of drafts to try.

optstable?Same as generate().

→ table?Best result across K attempts.