Measurement-conditioned classical control

Purpose and scope

Adds verification and provenance above existing measurement-conditioned classical control. It does not rename the baseline if (bit == 0|1) behavior as a new feature.

Core design rules

• Extended predicates use a closed logical subset over measurement-derived values and do not include arbitrary arithmetic.
• Branch-exhaustive outcome invariants and randomness consumption receive explicit rules.
• Seeded branch records and replay are supported by independent checks such as deferred-measurement equivalence.

Example from the original

This example illustrates the design recorded in the original. It is not by itself a claim of executable or stable support; check required options and the current version.

circuit teleport(q: QReg<3>) {
  H(q[1]);
  CNOT(q[1], q[2]);

  CNOT(q[0], q[1]);
  H(q[0]);

  let m0 = measure(q[0]);
  let m1 = measure(q[1]);

  if (m1 == 1) { X(q[2]); }
  if (m0 == 1) { Z(q[2]); }

  assert_branch_invariant(q[2]);
}

Limits and interpretation

• This scope is forbidden in oracle bodies and defines no physical latency or provider feed-forward contract.
• Draft status in the source does not mean existing simple conditionals are being removed.

Status and implementation boundary

The source is recorded as a draft. Distinguish extended control from baseline conditions and evaluate negotiated options, seed and branch traces together when reviewing execution evidence.