Function asBigint

src/compute-engine/boxed-expression/numerics.ts:78–115

(
  x: Complex | BigDecimal | ExpressionInput | undefined
)

  return bn / bd;
}

export function asBigint(
  x: Complex | BigDecimal | ExpressionInput | undefined
): bigint | null {
  if (x === undefined || x === null) return null;

  if (typeof x === 'bigint') return x;
  if (typeof x === 'number' && Number.isInteger(x)) return BigInt(x);

  if (isExpression(x)) {
    if (!isNumber(x)) return null;
    const num = x.numericValue;

    if (typeof num === 'number') {
      if (Number.isInteger(num)) return BigInt(num);
      return null;
    }

    // Extract the exact integer without a precision-limited round-trip.
    const exact = exactIntegerValue(num);
    if (exact !== null) return exact;

    if (num.im !== 0) return null;

    // Not an exact integer: only accept a genuine integer-valued float.
    if (!Number.isInteger(num.re)) return null;

    return BigInt(num.re);
  }

  if (x instanceof BigDecimal || typeof x === 'string') return bigint(x);

  if (x instanceof Complex) {
    if (x.im === 0) return bigint(x.re);
    return null;
  }

  return bigintValue(x as MathJsonExpression);
}

export function asBignum(expr: Expression | undefined): BigDecimal | null {