Has translation

@param string $key
@param string $lang
@return bool
504866
public static function has($key, $lang = null)
    {
        $lang = $lang ?: static::$lang;
        return isset(static::$langs[$lang][$key]);
    }
132925
public function required($input, $key, $lang)
    {
        $lang = $this->custom('required', $lang);
        if (empty($input[$key])) {
            return str_replace(':field', $key, $lang);
        }
    }
730745
protected static function translate($key)
    {
        if (is_callable(static::getTranslatorFunction())) {
            $translated = call_user_func(static::getTranslatorFunction(), $key);
            if ($key !== $translated) {
                return $translated;
            } else {
                return '';
            }
        } else {
            return '';
        }
    }
739955
private function Lang($key) {
    if(count($this->language) < 1) {
      $this->SetLanguage('en'); // set the default language
    }

    if(isset($this->language[$key])) {
      return $this->language[$key];
    } else {
      return 'Language string failed to load: ' . $key;
    }
  }
257828
public function t(string $key, array $args = [], $lang = '')
    {
        return $this->translate($key, $args, $lang);
    }
670542
public function get($key, $alternative=null, $lang=null){

        if (!$lang) {
            $lang = $this->locale;
        }

        if (!$alternative){
            $alternative = $key;
        }

        return isset($this->_languages[$lang][$key]) ? $this->_languages[$lang][$key]:$alternative;
    }
707491
public function tl($key, array $args = [], $lang = null)
    {
        return $this->translate($key, $args, $lang);
    }
984102
public function has(string $key) : bool
    {
        $k = $this->keyConvert($key);
        return getenv($k) !== false;
    }
419000
public function has(string $key): bool
    {
        $this->checkConnection(__METHOD__);
        return $this->engine->has($key);
    }
114711
protected function accessBlob( $domain, $lang, $key ) {
		if ( !isset( $this->messageBlob[$domain][$lang][$key] ) ) {
			return null;
		}
		return $this->messageBlob[$domain][$lang][$key];
	}
923633
public function translate($key)
    {
        if ($this->translations === null) {
            $this->loadTranslations();
        }

        if (!isset($this->translations[$key])) {
            // the key if $this is already the fallback translator
            return $this !== self::$fallbackTranslator ? self::$fallbackTranslator->translate($key) : $key;
        }

        return  $this->translations[$key];
    }
40920
public function has($key, $locale = null, $driver = null) {
        $driver = ! is_null($driver) ? $this->getDriver($driver) : $this->driver();

        return $driver
            ->has($key, $locale);
    }
580954
public function translation_exists($lang, $includeall = true) {
        $translations = $this->get_list_of_translations($includeall);
        return isset($translations[$lang]);
    }
308360
public function has($target, $language)
    {
        $key = $target->getId().'_'.$language;

        return isset($this->items[$key]);
    }
460390
public function has($key, $locale = null, $fallback = true)
    {
        return $this->get($key, array(), $locale, $fallback) !== $key;
    }
308474
function keyTranslate( $key )
    {
        $msg = $this->findKey( $key );
        if ( $msg !== null )
            return $msg["translation"];
        else
        {
            return null;
        }
    }
1133108
public function isAvailableLanguage($lang)
    {
        return array_key_exists($lang, $this->getLoader()->getOption('available_languages')) ||
            in_array($lang, $this->getLoader()->getOption('available_languages'));
    }