Typed classical values

Purpose and scope

Adds a bounded, typed, immutable value layer between measurement and classical computation. Aggregating measured bits and making conversions explicit avoids relying on incidental JavaScript coercion.

Core design rules

• Fixed-size arrays and bit vectors carry an element type and a declared length.
• Conversions from bits to numerical values use explicit operations; type labels are not merely comments.
• AST, runtime and result evidence must retain the same type information.

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.

module typed_measurement_summary;
@seed(17);

fn main() {
  let q: QReg<3> = qreg[3];
  H(q[0]);
  CNOT(q[0], q[1]);

  let a: Bit = measure(q[0]);
  let b: Bit = measure(q[1]);
  let c: Bit = measure(q[2]);

  let outcomes: Array<Bit, 3> = [a, b, c];
  let encoded: Int = bits_to_int(outcomes);
  let ones: Int = count_ones(outcomes);
  let ratio: Float = int_to_float(ones) / 3.0;
  let weights: Array<Float, 3> = [1.0, 2.0, 3.0];
  let average: Float = mean(weights);
  return encoded;
}

Limits and interpretation

• Runtime-growing collections and general mutable memory are outside this slice.
• A classical value after measurement does not represent the complete pre-measurement quantum state.

Status and implementation boundary

The source describes a runtime-experimental value contract. Read NM-RFC-0035 and the current guides separately for classical helpers and subsequent numeric additions.