Struct ProverTranscript 

pub struct ProverTranscript<'a, C, F: TranscriptField, EF> { /* private fields */ }

Prover-side transcript of one batch of quadratic sumcheck rounds.

Overview

Holds the only definition of what a prover writes per round.

Every prover of these rounds drives them through this type. No two prover loops can then drift from each other, or from the verifier.

Borrowing

The challenger is borrowed, not consumed.

A sumcheck runs inside a larger protocol. That protocol’s own transcript continues where this one stops.

Implementations

impl<'a, C, F, EF> ProverTranscript<'a, C, F, EF>

where F: TranscriptField, EF: ExtensionField<F>, C: CanObserve<F> + CanSample<F> + GrindingChallenger<Witness = F>,

pub fn new(challenger: &'a mut C, shape: SumcheckShape) -> Self

Seed the transcript from the shape.

A batch of zero rounds leaves the sponge exactly as it was found.

Arguments

• challenger: sponge of the surrounding protocol, borrowed for the batch.
• shape: the numbers that fix this batch’s transcript.

pub fn round(&mut self, c_a: EF, c_inf: EF) -> (EF, Option<F>)

Play one round: bind the two transmitted values, grind, and draw the challenge.

Returns

• The challenge that binds this round’s variable.
• The grinding witness, when the difficulty is positive.

The caller stores both in its own proof.

Panics

When the batch was described with no rounds at all.

pub fn finish(self)

Close the transcript once every described step has been played.

Panics

When fewer rounds were played than the batch was described with.