src/Checkers/Traits/CompiledBlacklistAwareTrait.php
protected function errorIfCompiledBlacklistIsEmpty(Config $config): ?Error
    {
        $blacklist = $config->compileBlacklist();

        return empty($blacklist)
            ? ResultFactory::makeError($this, 'Blacklist is empty.')
            : null;
    }
protected function errorIfCompiledBlacklistIsEmpty(Config $config): ?Error
    {
        $blacklist = $config->compileBlacklist();

        return empty($blacklist)
            ? ResultFactory::makeError($this, 'Blacklist is empty.')
            : null;
    }
protected function errorIfCompiledBlacklistIsEmpty ( Config $ config ) : ? Error { $ blacklist = $ config -> compileBlacklist ( ) ; return empty ( $ blacklist ) ? ResultFactory :: makeError ( $ this , 'Blacklist is empty.' ) : null ; }
Returns error if compiled blacklist is empty.

@param Config $config The config instance.

@return Error|null
Returns error if compiled blacklist is empty .