*
     * @return bool
     */
    private static function isValidName(string $name)
    {
        return Regex::matches('~(*UTF8)\A[\p{Ll}\p{Lu}\p{M}\p{N}_.]+\z~', $name)->success()->getOrElse(false);
    }

    /**
     * Parse the given variable value.
     *
     * This has the effect of stripping quotes and comments, dealing with
     * special characters, and locating nested variables, but not resolving
     * them. Formally, we run a finite state automaton with an output tape: a
     * transducer. We wrap the answer in a result type.
     *
     * @param string $value
     *
     * @return \GrahamCampbell\ResultType\Result<\Dotenv\Parser\Value, string>
     */
    private static function parseValue(string $value)
    {
        if (\trim($value) === '') {
            /** @var \GrahamCampbell\ResultType\Result<\Dotenv\Parser\Value, string> */
            return Success::create(Value::blank());
        }

        return \array_reduce(\iterator_to_array(Lexer::lex($value)), static function (Result $data, string $token) {
            return $data->flatMap(static function (array $data) use ($token) {
                return self::processToken($data[1], $token)->map(static function (array $val) use ($data) {
                    return [$data[0]->append($val[0], $val[1]), $val[2]];
                });
            });
        }, Success::create([Value::blank(), self::INITIAL_STATE]))->flatMap(static function (array $result) {
            /** @psalm-suppress DocblockTypeContradiction */
            if (in_array($result[1], self::REJECT_STATES, true)) {
                /** @var \GrahamCampbell\ResultType\Result<\Dotenv\Parser\Value, string> */
                return Error::create('a missing closing quote');
            }

            /** @var \GrahamCampbell\ResultType\Result<\Dotenv\Parser\Value, string> */
            return Success::create($result[0]);
        })->mapError(static function (string $err) use ($value) {
            return self::getErrorMessage($err, $value);
        });
    }

    /**
     * Process the given token.
     *
     * @param int    $state
     * @param string $token
     *
     * @return \GrahamCampbell\ResultType\Result<array{string, bool, int}, string>
     */
    private static function processToken(int $state, string $token)
    {
        switch ($state) {
            case self::INITIAL_STATE:
                if ($token === '\'') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::SINGLE_QUOTED_STATE]);
                } elseif ($token === '"') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::DOUBLE_QUOTED_STATE]);
                } elseif ($token === '#') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::COMMENT_STATE]);
                } elseif ($token === '$') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create([$token, true, self::UNQUOTED_STATE]);
                } else {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create([$token, false, self::UNQUOTED_STATE]);
                }
            case self::UNQUOTED_STATE:
                if ($token === '#') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::COMMENT_STATE]);
                } elseif (\ctype_space($token)) {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::WHITESPACE_STATE]);
                } elseif ($token === '$') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create([$token, true, self::UNQUOTED_STATE]);
                } else {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create([$token, false, self::UNQUOTED_STATE]);
                }
            case self::SINGLE_QUOTED_STATE:
                if ($token === '\'') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::WHITESPACE_STATE]);
                } else {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create([$token, false, self::SINGLE_QUOTED_STATE]);
                }
            case self::DOUBLE_QUOTED_STATE:
                if ($token === '"') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::WHITESPACE_STATE]);
                } elseif ($token === '\\') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::ESCAPE_SEQUENCE_STATE]);
                } elseif ($token === '$') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create([$token, true, self::DOUBLE_QUOTED_STATE]);
                } else {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create([$token, false, self::DOUBLE_QUOTED_STATE]);
                }
            case self::ESCAPE_SEQUENCE_STATE:
                if ($token === '"' || $token === '\\') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create([$token, false, self::DOUBLE_QUOTED_STATE]);
                } elseif ($token === '$') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create([$token, false, self::DOUBLE_QUOTED_STATE]);
                } else {
                    $first = Str::substr($token, 0, 1);
                    if (\in_array($first, ['f', 'n', 'r', 't', 'v'], true)) {
                        /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                        return Success::create([\stripcslashes('\\'.$first).Str::substr($token, 1), false, self::DOUBLE_QUOTED_STATE]);
                    } else {
                        /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                        return Error::create('an unexpected escape sequence');
                    }
                }
            case self::WHITESPACE_STATE:
                if ($token === '#') {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::COMMENT_STATE]);
                } elseif (!\ctype_space($token)) {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Error::create('unexpected whitespace');
                } else {
                    /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                    return Success::create(['', false, self::WHITESPACE_STATE]);
                }
            case self::COMMENT_STATE:
                /** @var \GrahamCampbell\ResultType\Result<array{string, bool, int}, string> */
                return Success::create(['', false, self::COMMENT_STATE]);
            default:
                throw new \Error('Parser entered invalid state.');
        }
    }

    /**
     * Generate a friendly error message.
     *
     * @param string $cause
     * @param string $subject
     *
     * @return string
     */
    private static function getErrorMessage(string $cause, string $subject)
    {
        return \sprintf(
            'Encountered %s at [%s].',
            $cause,
            \strtok($subject, "\n")
        );
    }
}
<br />
<b>Fatal error</b>:  Uncaught ReflectionException: Class &quot;config&quot; does not exist in /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php:959
Stack trace:
#0 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php(959): ReflectionClass-&gt;__construct('config')
#1 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php(832): Illuminate\Container\Container-&gt;build('config')
#2 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Application.php(1078): Illuminate\Container\Container-&gt;resolve('config', Array, true)
#3 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php(763): Illuminate\Foundation\Application-&gt;resolve('config', Array)
#4 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Application.php(1058): Illuminate\Container\Container-&gt;make('config', Array)
#5 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php(1580): Illuminate\Foundation\Application-&gt;make('config')
#6 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Log/LogManager.php(580): Illuminate\Container\Container-&gt;offsetGet('config')
#7 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Log/LogManager.php(631): Illuminate\Log\LogManager-&gt;getDefaultDriver()
#8 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Log/LogManager.php(126): Illuminate\Log\LogManager-&gt;parseDriver(NULL)
#9 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Log/LogManager.php(701): Illuminate\Log\LogManager-&gt;driver()
#10 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Exceptions/Handler.php(380): Illuminate\Log\LogManager-&gt;error('Class &quot;Dotenv\\P...', Array)
#11 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Exceptions/Handler.php(343): Illuminate\Foundation\Exceptions\Handler-&gt;reportThrowable(Object(Error))
#12 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(563): Illuminate\Foundation\Exceptions\Handler-&gt;report(Object(Error))
#13 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(147): Illuminate\Foundation\Http\Kernel-&gt;reportException(Object(Error))
#14 /home/systemkol/public_html/index.php(59): Illuminate\Foundation\Http\Kernel-&gt;handle(Object(Illuminate\Http\Request))
#15 {main}

Next Illuminate\Contracts\Container\BindingResolutionException: Target class [config] does not exist. in /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php:961
Stack trace:
#0 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php(832): Illuminate\Container\Container-&gt;build('config')
#1 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Application.php(1078): Illuminate\Container\Container-&gt;resolve('config', Array, true)
#2 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php(763): Illuminate\Foundation\Application-&gt;resolve('config', Array)
#3 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Application.php(1058): Illuminate\Container\Container-&gt;make('config', Array)
#4 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php(1580): Illuminate\Foundation\Application-&gt;make('config')
#5 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Log/LogManager.php(580): Illuminate\Container\Container-&gt;offsetGet('config')
#6 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Log/LogManager.php(631): Illuminate\Log\LogManager-&gt;getDefaultDriver()
#7 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Log/LogManager.php(126): Illuminate\Log\LogManager-&gt;parseDriver(NULL)
#8 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Log/LogManager.php(701): Illuminate\Log\LogManager-&gt;driver()
#9 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Exceptions/Handler.php(380): Illuminate\Log\LogManager-&gt;error('Class &quot;Dotenv\\P...', Array)
#10 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Exceptions/Handler.php(343): Illuminate\Foundation\Exceptions\Handler-&gt;reportThrowable(Object(Error))
#11 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(563): Illuminate\Foundation\Exceptions\Handler-&gt;report(Object(Error))
#12 /home/systemkol/source/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(147): Illuminate\Foundation\Http\Kernel-&gt;reportException(Object(Error))
#13 /home/systemkol/public_html/index.php(59): Illuminate\Foundation\Http\Kernel-&gt;handle(Object(Illuminate\Http\Request))
#14 {main}
  thrown in <b>/home/systemkol/source/vendor/laravel/framework/src/Illuminate/Container/Container.php</b> on line <b>961</b><br />