BitcoinCurrencies.php

<?php
 
namespace Money\Currencies;
 
use Money\Currencies;
use Money\Currency;
use Money\Exception\UnknownCurrencyException;
 
final class BitcoinCurrencies implements Currencies
{
    const CODE = 'XBT';
 
    const SYMBOL = "\xC9\x83";
 
    public function contains(Currency $currency)
    {
        return self::CODE === $currency->getCode();
    }
 
    public function subunitFor(Currency $currency)
    {
        if ($currency->getCode() !== self::CODE) {
            throw new UnknownCurrencyException(
                $currency->getCode().' is not bitcoin and is not supported by this currency repository'
            );
        }
 
        return 8;
    }
 
    public function getIterator()
    {
        return new \ArrayIterator([new Currency(self::CODE)]);
    }
}