/**
 * string や number を bigint に変換
 * Convert string, number, etc... to bigint
 *
 * @example
 * ```ts
 * bigintize('123') // BigInt(123)
 * bigintize(123) // BigInt(123)
 * bigintize('$1,000') // BigInt(1000)
 * bigintize(NaN) // throw error
 * bigintize('invalid value') // throw error
 * bigintize('invalid value', BitInt(1)) // BitInt(1)
 * ```
 * @param v 変換元の値 <br /> value to convert
 * @param d 変換に失敗した場合に返す値 <br /> value to return if conversion fails
 * @returns
 */
export declare function bigintize(v: unknown, d?: bigint): bigint;