Function integerRangeIterator

src/compute-engine/library/sets.ts:1485–1495

(
  ce: ComputeEngine,
  start: number,
  step: number
)

  }
  const name = labelSymbolName(expr);
  return name !== null && /^[A-Z]/.test(name);
}

/** Validate `args` against `signature`, but keep label operands (see
 * `isLabelOperand`) as-is where validation flagged them. */
function validateSetArguments(
  ce: ComputeEngine,
  args: ReadonlyArray<Expression>,
  signature: string
): ReadonlyArray<Expression> {
  const validated = validateArguments(ce, args, parseType(signature));
  if (!validated) return args;
  return validated.map((v, i) =>
    !v.isValid && isLabelOperand(args[i]) ? args[i] : v